fp6-vendor-blobs: the checksum the extractor change forgot, and a check that finds the next one in a second

CI run 52 failed at minute 57 with `fp6-vendor-blobs-extract: FAILED` from
abuild's checksum verification: 9575e55 changed the extractor and left its
sha512sums entry alone. Nothing was installed or published; latest is the
run-51 image.

Fix the sum, and stop paying an hour to learn it. check-aports.sh sources
every APKBUILD under aports/ and compares the committed sha512sums of its
local source files (scripts, units, configs, patches, including ones in a
subdirectory) against the files themselves. build.sh runs it before
pmbootstrap touches anything, so this class of mistake now fails in the first
seconds of a run and prints the line to paste. Aports whose sums build.sh
regenerates with pmbootstrap checksum are read from build.sh and skipped, so
the two lists cannot drift.

Verified: the checker reports exactly the run-52 mismatch on the tree as
pushed and nothing on the tree as fixed; a scratch copy with one corrupted
sum is caught; the fixed aport builds under abuild in an alpine:edge
container (the only complaint was the throwaway signing key at the index
step, which the CI's pmbootstrap flow does not have).

aports/device/fp6-vendor-blobs/APKBUILD

@@ -55,7 +55,7 @@ package() {
 }
 
 sha512sums="
-a71b2c86f980734d0aae6e135b26272fe52ae5603050bea52f55f7e74c8bd98c62b6194047711248d4fef40851792adc47d77c40016d99a0d68ecd2459894b80  fp6-vendor-blobs-extract
+2caafdedf93e103516834a1f815dd828ecee66c82d569e4a925ccc6bd6ac75d6778290adb02db69538af3bb6ad36cee5c13c8afba2c722a4c4550efe761ba8a0  fp6-vendor-blobs-extract
 b4c290095d9f39515378dfef08de720ce49324210342aa13c131dfce1103785e796e6f821f0c659671a4c44b46f466ce0e03f11f216fdcdee2a99db5e7970800  fp6-vendor-blobs.service
 9e79dd0aed13f11a71282aa24b2a26331e85c105e25ab0c0fed6189b8c300769a5f4308b18b91d9855868d658ad3a57c03e26c9b11bd27fd5e03f9a5decbbd6a  fp6-vendor-blobs.preset
 "