efi: Move inline functions to unconditional part of header

efi: Move inline functions to unconditional part of header

At present these two functions are defined in efi_loader.h but only if
CONFIG_EFI_LOADER is enabled. But these are functions that are useful to
other code, such as that which deals with Intel Handoff Blocks (HOBs).

Move these to the top of the function.

Possibly ascii2unicode() should not be an inline function, since this
might impact code size.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>