Add kernel 5.15 for RPI4 support

root/target/linux/bcm27xx/patches-5.15/0482-media-i2c-tc358743-Fix-compiler-warning.patch

@@ -0,0 +1,29 @@
+From 4ecfdd7258196879edb69f087b02419e68d8dd4c Mon Sep 17 00:00:00 2001
+From: Phil Elwell <phil@raspberrypi.com>
+Date: Tue, 27 Jul 2021 11:17:08 +0100
+Subject: [PATCH 482/634] media: i2c: tc358743: Fix compiler warning
+
+Avoid a compiler warning by using the "fallthrough" pseudo-keyword in
+place of the old "/* fall through */" comment convention.
+
+Signed-off-by: Phil Elwell <phil@raspberrypi.com>
+---
+ drivers/media/i2c/tc358743.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/drivers/media/i2c/tc358743.c b/drivers/media/i2c/tc358743.c
+index da166e6a41d6..e3de5b213e05 100644
+--- a/drivers/media/i2c/tc358743.c
++++ b/drivers/media/i2c/tc358743.c
+@@ -2008,7 +2008,7 @@ static int tc358743_probe_of(struct tc358743_state *state)
+ 	switch (bps_pr_lane) {
+ 	default:
+ 		dev_warn(dev, "untested bps per lane: %u bps\n", bps_pr_lane);
+-		/* fall through */
++		fallthrough;
+ 	case 594000000U:
+ 		state->pdata.lineinitcnt = 0xe80;
+ 		state->pdata.lptxtimecnt = 0x003;
+-- 
+2.33.1
+