staging: sm750fb: Add braces around if statement.

Added braces around if statement. This patch fixes the following
checkpatch issue:

CHECK: braces {} should be used on all arms of this statement

Signed-off-by: Varsha Rao <rvarsha016@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>