ARM: l2c: print a warning with L2C-310 caches if the cache size is modified

As we have now removed all instances of the L2C-310 having its cache
size "modified" via platform/SoC code, discourage new cases showing
up by printing a warning.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mm/cache-l2x0.c

@@ -765,6 +765,8 @@ static void __init __l2c_init(const struct l2c_init_data *data,
 	/* Determine the number of ways */
 	switch (cache_id & L2X0_CACHE_ID_PART_MASK) {
 	case L2X0_CACHE_ID_PART_L310:
+		if ((aux_val | ~aux_mask) & (L2C_AUX_CTRL_WAY_SIZE_MASK | L310_AUX_CTRL_ASSOCIATIVITY_16))
+			pr_warn("L2C: DT/platform tries to modify or specify cache size\n");
 		if (aux & (1 << 16))
 			ways = 16;
 		else