usb: musb: davinci: fix build breakage

usb: musb: davinci: fix build breakage

Commit 95836e82bc04e328c75598e4387b3b9142833098 (ARM: mach-davinci:
remove mach/memory.h) removed mach/memory.h for DaVinci which broke
DaVinci MUSB build.

mach/memory.h is not actually needed in davinci.c, so remove it.
While at it, also remove some more machine specific inclulde
files which are not needed for build.

Tested on DM644x EVM using USB card reader.

Cc: stable@vger.kernel.org # v3.2
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>