ARM: l2c: fix revision checking

The revision checking in l2c310_enable() was not correct; we were
masking the part number rather than the revision number.  Fix this
to use the correct macro.

Fixes: 4374d649 ("ARM: l2c: add automatic enable of early BRESP")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mm/cache-l2x0.c

@@ -664,7 +664,7 @@ static int l2c310_cpu_enable_flz(struct notifier_block *nb, unsigned long act, v
 
 static void __init l2c310_enable(void __iomem *base, u32 aux, unsigned num_lock)
 {
-	unsigned rev = readl_relaxed(base + L2X0_CACHE_ID) & L2X0_CACHE_ID_PART_MASK;
+	unsigned rev = readl_relaxed(base + L2X0_CACHE_ID) & L2X0_CACHE_ID_RTL_MASK;
 	bool cortex_a9 = read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9;
 
 	if (rev >= L310_CACHE_ID_RTL_R2P0) {