kernel: Move to Linux v5.3.1-openpower1

This is the first v5.3 based kernel.

See https://kernelnewbies.org/Linux_5.3 for notable upstream changes
made for this release.

Signed-off-by: Joel Stanley <joel@jms.id.au>
diff --git a/openpower/linux/0002-Release-OpenPower-kernel.patch b/openpower/linux/0002-Release-OpenPower-kernel.patch
index b5f44c8..01f56f3 100644
--- a/openpower/linux/0002-Release-OpenPower-kernel.patch
+++ b/openpower/linux/0002-Release-OpenPower-kernel.patch
@@ -9,13 +9,13 @@
  1 file changed, 1 insertion(+), 1 deletion(-)
 
 diff --git a/Makefile b/Makefile
-index 32226d81fbb5..390611701d38 100644
+index f32e8d2e09c3..8fbcdcb2d96b 100644
 --- a/Makefile
 +++ b/Makefile
 @@ -2,7 +2,7 @@
  VERSION = 5
- PATCHLEVEL = 2
- SUBLEVEL = 17
+ PATCHLEVEL = 3
+ SUBLEVEL = 1
 -EXTRAVERSION =
 +EXTRAVERSION = -openpower1
  NAME = Bobtail Squid