tweaks: allow the linter to be used in view mode, as it makes no changes

The linter has been marked as NOVIEW since it was introduced in 2.3.3.
But that was a mistake, as the tool does not change the buffer contents.

This addresses a minor part of https://savannah.gnu.org/bugs/?62903.

src/nano.c

@@ -1386,7 +1386,7 @@ bool changes_something(const void *f)
 			f == do_spell ||
 #endif
 #ifdef ENABLE_COLOR
-			f == do_linter || f == do_formatter ||
+			f == do_formatter ||
 #endif
 #ifdef ENABLE_WORDCOMPLETION
 			f == complete_a_word ||