genksyms: simplify usage of find_symbol()

Allow searching for symbols of an exact type. The lexer does this and a
subsequent patch will add one more usage.

Signed-off-by: Michal Marek <mmarek@suse.cz>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
diff --git a/scripts/genksyms/lex.c_shipped b/scripts/genksyms/lex.c_shipped
index d0a0423..f231c08 100644
--- a/scripts/genksyms/lex.c_shipped
+++ b/scripts/genksyms/lex.c_shipped
@@ -2347,8 +2347,7 @@
 	      }
 	    if (!suppress_type_lookup)
 	      {
-		struct symbol *sym = find_symbol(yytext, SYM_TYPEDEF);
-		if (sym && sym->type == SYM_TYPEDEF)
+		if (find_symbol(yytext, SYM_TYPEDEF, 1))
 		  token = TYPE;
 	      }
 	  }