bcm27xx: Remove unneeded kernel patch

This problem was fixed upstream in a different way, see:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=linux-6.1.y&id=f434703fb893ddffcdbc1eec7646ce321e1190a8

Remove this now obsolete patch.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

target/linux/bcm27xx/patches-6.1/950-0146-sc16is7xx-Don-t-spin-if-no-data-received.patch

@@ -1,23 +0,0 @@
-From 1f9195cda30b320038cf94b4d14f85e58dd69d6d Mon Sep 17 00:00:00 2001
-From: Phil Elwell <phil@raspberrypi.org>
-Date: Tue, 6 Nov 2018 12:57:48 +0000
-Subject: [PATCH] sc16is7xx: Don't spin if no data received
-
-See: https://github.com/raspberrypi/linux/issues/2676
-
-Signed-off-by: Phil Elwell <phil@raspberrypi.org>
----
- drivers/tty/serial/sc16is7xx.c | 2 ++
- 1 file changed, 2 insertions(+)
-
---- a/drivers/tty/serial/sc16is7xx.c
-+++ b/drivers/tty/serial/sc16is7xx.c
-@@ -783,6 +783,8 @@ static bool sc16is7xx_port_irq(struct sc
- 
- 			if (rxlen)
- 				sc16is7xx_handle_rx(port, rxlen, iir);
-+			else
-+				return false;
- 			break;
- 		/* CTSRTS interrupt comes only when CTS goes inactive */
- 		case SC16IS7XX_IIR_CTSRTS_SRC: