scripts: get_abi.pl: better handle escape chars on what:

The parser for the symbols defined on What: doesn't cover all
chars that need to be scaped, like '{' and '}'. Change the logic
to be more generic, and ensure that the same regex will be used
on both What: and when parsing the cross-references.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/29cb56def89b508fe605bcd2ba74a4376cc08e35.1616668017.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/scripts/get_abi.pl b/scripts/get_abi.pl
index 92d9aa6..a9348b9 100755
--- a/scripts/get_abi.pl
+++ b/scripts/get_abi.pl
@@ -283,6 +283,7 @@
 
 # \b doesn't work well with paths. So, we need to define something else
 my $bondary = qr { (?<![\w\/\`\{])(?=[\w\/\`\{])|(?<=[\w\/\`\{])(?![\w\/\`\{]) }x;
+my $symbols = qr { ([\x01-\x08\x0e-\x1f\x21-\x2f\x3a-\x40\x7b-\xff]) }x;
 
 sub output_rest {
 	create_labels();
@@ -305,7 +306,6 @@
 		}
 
 		my $w = $what;
-		$w =~ s/([\(\)\_\-\*\=\^\~\\])/\\$1/g;
 
 		if ($type ne "File") {
 			my $cur_part = $what;
@@ -329,6 +329,7 @@
 			my $len = 0;
 
 			foreach my $name (@names) {
+				$name =~ s/$symbols/\\$1/g;
 				$name = "**$name**";
 				$len = length($name) if (length($name) > $len);
 			}
@@ -395,7 +396,7 @@
 					if (defined($data{$s}) && defined($data{$s}->{label})) {
 						my $xref = $s;
 
-						$xref =~ s/([\x00-\x1f\x21-\x2f\x3a-\x40\x7b-\xff])/\\$1/g;
+						$xref =~ s/$symbols/\\$1/g;
 						$xref = ":ref:`$xref <" . $data{$s}->{label} . ">`";
 
 						$desc =~ s,$bondary$s$bondary,$xref,g;