ARM: omap3: Remove hand-encoded SMC instructions

For various reasons, Linux now only officially supports being built
with tools which are new enough to understand the SMC instruction.

Replacing the hand-encoded instructions when the mnemonic also
allows for correct assembly in Thumb-2 (otherwise, the result is
random data in the middle of the code).

The Makefile already ensures that this file is built with a high
enough gcc -march= flag (armv7-a).

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Jean Pihet <j-pihet@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>