mediatek: fix patch filename

A previous commit wrongly renamed a patch file omitting the final 'h'
character. Rename it to again have the correct '.patch' suffix.

Fixes: c23b9256f0 ("mediatek: replace patches with upstream version")
Signed-off-by: Daniel Golle <daniel@makrotopia.org>

diff --git a/target/linux/mediatek/patches-6.12/181-v6.16-arm64-dts-mediatek-mt7988a-bpi-r4-configure-spi-node.patc b/target/linux/mediatek/patches-6.12/181-v6.16-arm64-dts-mediatek-mt7988a-bpi-r4-configure-spi-node.patch
similarity index 100%
rename from target/linux/mediatek/patches-6.12/181-v6.16-arm64-dts-mediatek-mt7988a-bpi-r4-configure-spi-node.patc
rename to target/linux/mediatek/patches-6.12/181-v6.16-arm64-dts-mediatek-mt7988a-bpi-r4-configure-spi-node.patch