armv7: Make lowlevel_init.S's lowlevel_init do ABI compatible stack

Make sure that when we setup the stack before calling s_init() we have
the stack have 8-byte alignment for ABI compliance.

Tested-by: Allen Martin <amartin@nvidia.com>
Signed-off-by: Tom Rini <trini@ti.com>

arch/arm/cpu/armv7/lowlevel_init.S

@@ -36,6 +36,7 @@ ENTRY(lowlevel_init)
 	 * Setup a temporary stack
 	 */
 	ldr	sp, =CONFIG_SYS_INIT_SP_ADDR
+	bic	sp, sp, #7 /* 8-byte alignment for ABI compliance */
 
 	/*
 	 * Save the old lr(passed in ip) and the current lr to stack