misc: Fix build GCC-4.7 build errors

Error: selected processor does not support ARM mode `smc #0'
error: DIV usage mismatch between arch/arm/boot/compressed/head.o and output
error: DIV usage mismatch between arch/arm/boot/compressed/misc.o and output
error: DIV usage mismatch between arch/arm/boot/compressed/decompress.o and output
error: DIV usage mismatch between arch/arm/boot/compressed/lib1funcs.o and output
error: DIV usage mismatch between arch/arm/boot/compressed/ashldi3.o and output

Change-Id: I1251b843bb9b4c74ba8039fd194e3aed2183cf5b
GCC 4.8 fixes

Signed-off-by: Bryan Smith <zarboz@gmail.com>
makefile: use linaro 4.8 toolchain