msm: Rip out fmem related memory adjustments

fmem is deprecated. Get rid of the special handling for
fmem in memory reservation code.

Change-Id: I24dc24cee364d992cbbe08d81851987d721a587b
Signed-off-by: Laura Abbott <lauraa@codeaurora.org>
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>