generic: 5.15: rename patches to match correct version

Rename two patches which were only accepted in Linux 6.2, but were
marked as if they were accepted in Linux 6.1.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

diff --git a/target/linux/generic/backport-5.15/890-v6.1-mtd-spinand-winbond-fix-flash-detection.patch b/target/linux/generic/backport-5.15/890-v6.2-mtd-spinand-winbond-fix-flash-detection.patch
similarity index 100%
rename from target/linux/generic/backport-5.15/890-v6.1-mtd-spinand-winbond-fix-flash-detection.patch
rename to target/linux/generic/backport-5.15/890-v6.2-mtd-spinand-winbond-fix-flash-detection.patch

diff --git a/target/linux/generic/backport-5.15/891-v6.1-mtd-spinand-winbond-add-W25N02KV.patch b/target/linux/generic/backport-5.15/891-v6.2-mtd-spinand-winbond-add-W25N02KV.patch
similarity index 100%
rename from target/linux/generic/backport-5.15/891-v6.1-mtd-spinand-winbond-add-W25N02KV.patch
rename to target/linux/generic/backport-5.15/891-v6.2-mtd-spinand-winbond-add-W25N02KV.patch