[Flang][NFC] Fix typo (llvm#130960)

This was mainly a test of the pre-merge CI, but merging it since it fixes an actual typo.

Author: Meinersbur

flang/docs/F202X.md

@@ -291,7 +291,7 @@ functions whose implementations have very low priority: `SPLIT` and `TOKENIZE`.
 and could and should have been implemented once in some Fortran utility
 library for those who need a slow tokenization facility rather than
 requiring implementations in each vendor's runtime support library with
-all the extra cost and compatibilty risk that entails.
+all the extra cost and compatibility risk that entails.
 
 `SPLIT` is worse -- not only could it, like `TOKENIZE`,
 have been supplied by a Fortran utility library rather than being