Separate the remaining UEFI variable API functions GetNextVariableName and
QueryVariableInfo() from internal functions implementing them.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
We currently have two implementations of UEFI variables:
* variables provided via an OP-TEE module
* variables stored in the U-Boot environment
Read only variables are up to now only implemented in the U-Boot
environment implementation.
Provide a common interface for both implementations that allows handling
read-only variables.
As variable access is limited to very few source files put variable
related definitions into new include efi_variable.h instead of efi_loader.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
