README: Convert HTTP links to HTTPS

Convert all the other http:// links to https:// .
www.denx.de/twiki/ seems to move to www.denx.de/wiki/ ,
so change it.

I checked all links in this patch are valid.

Signed-off-by: Naoki Hayama <naoki.hayama@lineo.co.jp>

README

@@ -72,7 +72,7 @@ Where we come from:
 ===================
 
 - start from 8xxrom sources
-- create PPCBoot project (http://sourceforge.net/projects/ppcboot)
+- create PPCBoot project (https://sourceforge.net/projects/ppcboot)
 - clean up code
 - make it easier to add custom boards
 - make it possible to add other [PowerPC] CPUs
@@ -81,10 +81,10 @@ Where we come from:
   * S-Record download
   * network boot
   * ATA disk / SCSI ... boot
-- create ARMBoot project (http://sourceforge.net/projects/armboot)
+- create ARMBoot project (https://sourceforge.net/projects/armboot)
 - add other CPU families (starting with ARM)
-- create U-Boot project (http://sourceforge.net/projects/u-boot)
-- current project page: see http://www.denx.de/wiki/U-Boot
+- create U-Boot project (https://sourceforge.net/projects/u-boot)
+- current project page: see https://www.denx.de/wiki/U-Boot
 
 
 Names and Spelling:
@@ -606,7 +606,7 @@ The following options need to be configured:
 		This setting is mandatory for all boards that have only one
 		machine type and must be used to specify the machine type
 		number as it appears in the ARM machine registry
-		(see http://www.arm.linux.org.uk/developer/machines/).
+		(see https://www.arm.linux.org.uk/developer/machines/).
 		Only boards that have multiple machine types supported
 		in a single configuration file and the machine type is
 		runtime discoverable, do not have to use this setting.
@@ -3019,7 +3019,7 @@ Building U-Boot has been tested in several native build environments
 and in many different cross environments. Of course we cannot support
 all possibly existing versions of cross development tools in all
 (potentially obsolete) versions. In case of tool chain problems we
-recommend to use the ELDK (see http://www.denx.de/wiki/DULG/ELDK)
+recommend to use the ELDK (see https://www.denx.de/wiki/DULG/ELDK)
 which is extensively used to build and test U-Boot.
 
 If you are not using a native environment, it is assumed that you
@@ -4173,7 +4173,7 @@ consider minicom to be broken, and recommend not to use it. Under
 Unix, I recommend to use C-Kermit for general purpose use (and
 especially for kermit binary protocol download ("loadb" command), and
 use "cu" for S-Record download ("loads" command).  See
-http://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
+https://www.denx.de/wiki/view/DULG/SystemSetup#Section_4.3.
 for help with kermit.
 
 
@@ -4341,7 +4341,7 @@ On ARM, the following registers are used:
     Note: on ARM, only R_ARM_RELATIVE relocations are supported.
 
 On Nios II, the ABI is documented here:
-	http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
+	https://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
 
     ==> U-Boot will use gp to hold a pointer to the global data
 
@@ -4492,7 +4492,7 @@ int main(int argc, char *argv[])
 
 	while (learning) {
 		Read the README file in the top level directory;
-		Read http://www.denx.de/twiki/bin/view/DULG/Manual;
+		Read https://www.denx.de/wiki/bin/view/DULG/Manual;
 		Read applicable doc/README.*;
 		Read the source, Luke;
 		/* find . -name "*.[chS]" | xargs grep -i <keyword> */
@@ -4573,7 +4573,7 @@ Since the number of patches for U-Boot is growing, we need to
 establish some rules. Submissions which do not conform to these rules
 may be rejected, even when they contain important and valuable stuff.
 
-Please see http://www.denx.de/wiki/U-Boot/Patches for details.
+Please see https://www.denx.de/wiki/U-Boot/Patches for details.
 
 Patches shall be sent to the u-boot mailing list <u-boot@lists.denx.de>;
 see https://lists.denx.de/listinfo/u-boot