MIPS: Clear hazard between TagLo writes & cache ops

Writing to the coprocessor 0 TagLo registers introduces an execution
hazard in that we need that write to complete before any cache
instructions execute. Ensure that hazard is cleared by inserting an ehb
instruction between the TagLo writes & cache op loop.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>

arch/mips/lib/cache_init.S

@@ -293,6 +293,7 @@ l2_init:
 l1_init:
 	mtc0		zero, CP0_TAGLO
 	mtc0		zero, CP0_TAGLO, 2
+	ehb
 
 	/*
 	 * The caches are probably in an indeterminate state, so we force good