ARM: tegra: fix relocation truncated error when THUMB2_KERNEL enabled

The conditional branch instruction in Thumb2 only available to short range.
The linker will fail when the conditional branch over the range. Then
resulting in link error when generating kernel image. e.g.:

arch/arm/mach-tegra/reset-handler.S:47:(.text+0xf8e):
relocation truncated to fit: R_ARM_THM_JUMP19 against symbol
`cpu_resume' defined in .data section in arch/arm/kernel/built-in.o

This patch using a Thumb2 instruction IT (if-then) to have a longer branch
range.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Joseph Lo <josephl@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Dave Martin <dave.martin@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>