ARM: i.MX: Remove mach-cpuimx27sd board file

eukrea_mbimx27-baseboard.c and mach-cpuimx27.c can be replaced with their
devicetree equivalents: imx27-eukrea-mbimxsd27-baseboard.dts and
imx27-eukrea-cpuimx27.dtsi respectively, so remove the board files.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Acked-by: Eric Bénard <eric@eukrea.com>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>