ARM: 6766/1: Thumb-2: Reflect ARM/Thumb-2 configuration in module vermagic

Loading Thumb-2 modules into an ARM kernel or vice-versa isn't
guaranteed to work safely, since the kernel is not interworking-
aware everywhere.

This patch adds "thumb2" to the module vermagic when
CONFIG_THUMB2_KERNEL is enabled, to help avoid accidental loading
of modules into the wrong kernel.

Signed-off-by: Dave Martin <dave.martin@linaro.org>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>