ARM: imx6: fix v7_invalidate_l1 by adding I-Cache invalidation

The recent suspend/resume and reset testing on imx6q discovers that
not only D-Cache but also I-Cache has random data and validity when
the core comes out of a power recycle.

This patch adds I-Cache invalidation into v7_invalidate_l1 to make
sure both D-Cache and I-Cache invalidated on power-up.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>

arch/arm/mach-imx/head-v7.S

@@ -33,6 +33,7 @@
  */
 ENTRY(v7_invalidate_l1)
 	mov	r0, #0
+	mcr	p15, 0, r0, c7, c5, 0	@ invalidate I cache
 	mcr	p15, 2, r0, c0, c0, 0
 	mrc	p15, 1, r0, c0, c0, 0