generic: add bcm2835-rng quality patch

This patch allows devices without a high resolution timer to boot up faster.
It should speed up boots for bcm2708 and bcm63xx.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
(cherry-picked from commit 7747b3fa36)

target/linux/generic/pending-5.4/840-hwrng-bcm2835-set-quality-to-1000.patch

@@ -0,0 +1,26 @@
+From d6988cf1d16faac56899918bb2b1be8d85155e3f Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com>
+Date: Sat, 20 Feb 2021 18:36:38 +0100
+Subject: [PATCH] hwrng: bcm2835: set quality to 1000
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This allows devices without a high precission timer to reduce boot from >100s
+to <30s.
+
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+---
+ drivers/char/hw_random/bcm2835-rng.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/drivers/char/hw_random/bcm2835-rng.c
++++ b/drivers/char/hw_random/bcm2835-rng.c
+@@ -167,6 +167,7 @@ static int bcm2835_rng_probe(struct plat
+ 	priv->rng.init = bcm2835_rng_init;
+ 	priv->rng.read = bcm2835_rng_read;
+ 	priv->rng.cleanup = bcm2835_rng_cleanup;
++	priv->rng.quality = 1000;
+ 
+ 	if (dev_of_node(dev)) {
+ 		rng_id = of_match_node(bcm2835_rng_of_match, np);