improve 'typedef' patterns of find-doc-nits

Reviewed-by: Richard Levitte <levitte@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10673)

util/find-doc-nits

@@ -147,10 +147,10 @@ sub name_synopsis {
         if ( $line =~ /env (\S*)=/ ) {
             # environment variable env NAME=...
             $sym = $1;
-        } elsif ( $line =~ /typedef.*\(\*(\S+)\)\(.*/ ) {
+        } elsif ( $line =~ /typedef.*\(\*(\S+)\)\s*\(/ ) {
             # a callback function pointer: typedef ... (*NAME)(...
             $sym = $1;
-        } elsif ( $line =~ /typedef.* (\S+)\(.*/ ) {
+        } elsif ( $line =~ /typedef.* (\S+)\(/ ) {
             # a callback function signature: typedef ... NAME(...
             $sym = $1;
         } elsif ( $line =~ /typedef.* (\S+);/ ) {