Fix include paths include/linux and drivers/staging/android

Out-of-tree modules shouldn't have to add -I$(srctree)/include/linux to
their cflags. Instead, they should use the prefix "linux/" in their
 #include statements.

In addition, there don't appear to be any include files in
drivers/staging/android that this driver depends on, so let's remove the
related -I flag.

Signed-off-by: Daniel Mentz <danielmentz@google.com>
Change-Id: Idd63bc5bc4fef0e7948c2d4667364ae9b113f134