editors/emacs: Unbreak build after devel/tree-sitter update

When devel/tree-sitter was updated from version 0.25.10 to 0.26.7 in
19fa3d59c58, editors/emacs failed to build due to a breaking ABI change
introduced in tree-sitter 0.26.

Fix the build by patching Emacs to call tree-sitter's new function,
ts_language_abi_version, rather than the old ts_language_version. Both
functions have the same signature.

PR: 294144
Reported by: russo@bogodyn.org
Sponsored by: The FreeBSD Foundation