If a file does not exist, it should be created.
Fixes: f676b45151 ("fs: Add semihosting filesystem")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
This adds a filesystem which is backed by the host's filesystem. It is
modeled off of sandboxfs, which has very similar aims. Semihosting
doesn't support listing directories (except with SYS_SYSTEM), so neither
do we. it's possible to optimize a bit for the common case of reading a
whole file by omitting a call to smh_seek, but this is left as a future
optimization.
Signed-off-by: Sean Anderson <sean.anderson@seco.com>