[PATCH RESEND v2] checkpatch: use utf-8 match for spell checking

["Clément Le Goffic" <clement.legoffic@foss.st.com>]

From: Antonio Borneo <antonio.borneo@foss.st.com>

The current code that checks for misspelling verifies, in a more
complex regex, if $rawline matches [^\w]($misspellings)[^\w]

Being $rawline a byte-string, a utf-8 character in $rawline can
match the non-word-char [^\w].
E.g.:
	./scripts/checkpatch.pl --git 81c2f059ab9
	WARNING: 'ment' may be misspelled - perhaps 'meant'?
	#36: FILE: MAINTAINERS:14360:
	+M:     Clément Léger <clement.leger@bootlin.com>
	            ^^^^

Use a utf-8 version of $rawline for spell checking.

Signed-off-by: Antonio Borneo <antonio.borneo@foss.st.com>
Reported-by: Clément Le Goffic <clement.legoffic@foss.st.com>
---
Signed-off-by: Clément Le Goffic <clement.legoffic@foss.st.com>
---
- Link to v1: https://lore.kernel.org/lkml/20231212094310.3633-1-antonio.borneo@foss.st.com/
---
 scripts/checkpatch.pl | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 664f7b7a622c..489b74d52abe 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -3502,9 +3502,10 @@ sub process {
 # Check for various typo / spelling mistakes
 		if (defined($misspellings) &&
 		    ($in_commit_log || $line =~ /^(?:\+|Subject:)/i)) {
-			while ($rawline =~ /(?:^|[^\w\-'`])($misspellings)(?:[^\w\-'`]|$)/gi) {
+			my $rawline_utf8 = decode("utf8", $rawline);
+			while ($rawline_utf8 =~ /(?:^|[^\w\-'`])($misspellings)(?:[^\w\-'`]|$)/gi) {
 				my $typo = $1;
-				my $blank = copy_spacing($rawline);
+				my $blank = copy_spacing($rawline_utf8);
 				my $ptr = substr($blank, 0, $-[1]) . "^" x length($typo);
 				my $hereptr = "$hereline$ptr\n";
 				my $typo_fix = $spelling_fix{lc($typo)};

---
base-commit: e04c78d86a9699d136910cfc0bdcf01087e3267e
change-id: 20250616-b4-checkpatch-upstream-a8ef45ce0fc7

Best regards,
-- 
Clément Le Goffic <clement.legoffic@foss.st.com>