arm: rmobile: r8a7791: Fix initialize L2 cache

rmobile/lowlevel_init_ca15.S are common in r8a7790 and r8a7791 of
rmobile SoC. But L2 cache of r8a7791 does not use L2CTLR[5].
This adds fix to set L2CTLR [5] only when the r8a7790.

Signed-off-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
diff --git a/arch/arm/cpu/armv7/rmobile/lowlevel_init_ca15.S b/arch/arm/cpu/armv7/rmobile/lowlevel_init_ca15.S
index dbb96ed..5820e1a 100644
--- a/arch/arm/cpu/armv7/rmobile/lowlevel_init_ca15.S
+++ b/arch/arm/cpu/armv7/rmobile/lowlevel_init_ca15.S
@@ -53,7 +53,15 @@
 	cmp r1, #3			/* has already been set up */
 	bicne r0, r0, #0xe7
 	orrne r0, r0, #0x83		/* L2CTLR[7:6] + L2CTLR[2:0] */
-	orrne r0, r0, #0x20             /* L2CTLR[5] */
+
+	ldr	r2, =0xFF000044		/* PRR */
+	ldr	r1, [r2]
+	and	r1, r1, #0x7F00
+	lsrs	r1, r1, #8
+	cmp	r1, #0x45		/* 0x45 is ID of r8a7790 */
+	bne	L2CTLR_5_SKIP
+	orrne r0, r0, #0x20		/* L2CTLR[5] */
+L2CTLR_5_SKIP:
 	mcrne p15, 1, r0, c9, c0, 2
 
 _exit_init_l2_a15: