arch/arm/mach-omap2: replace strict_strto* with kstrto*

Replace obsolete strict_strto call with kstrto calls.
Simplify copy_from_user/strict_strto by using kstrto_from_user

Signed-off-by: Daniel Walter <dwalter@google.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>