ARM: 8327/1: zImage: add support for ARMv7-M

This patch makes it possible to enter zImage in Thumb mode for ARMv7-M
(Cortex-M) CPUs that do not support ARM mode. The kernel entry is also
made in Thumb mode.

[ukl: fix spelling in commit log, return early in call_cache_fn]

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Tested-by: Stefan Agner <stefan@agner.ch>
Tested-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/include/asm/unified.h b/arch/arm/include/asm/unified.h
index b88beab..200f9a7 100644
--- a/arch/arm/include/asm/unified.h
+++ b/arch/arm/include/asm/unified.h
@@ -24,6 +24,14 @@
 	.syntax unified
 #endif
 
+#ifdef CONFIG_CPU_V7M
+#define AR_CLASS(x...)
+#define M_CLASS(x...)	x
+#else
+#define AR_CLASS(x...)	x
+#define M_CLASS(x...)
+#endif
+
 #ifdef CONFIG_THUMB2_KERNEL
 
 #if __GNUC__ < 4