ecpg: Consistently use mm_strdup()

mm_strdup() is provided to check errors from strdup(), but some places
were failing to use it.

src/interfaces/ecpg/preproc/ecpg.addons

@@ -377,9 +377,9 @@ ECPG: opt_array_boundsopt_array_bounds'['']' block
 		$$.index1 = $1.index1;
 		$$.index2 = $1.index2;
 		if (strcmp($1.index1, "-1") == 0)
-			$$.index1 = strdup($3);
+			$$.index1 = mm_strdup($3);
 		else if (strcmp($1.index2, "-1") == 0)
-			$$.index2 = strdup($3);
+			$$.index2 = mm_strdup($3);
 		$$.str = cat_str(4, $1.str, mm_strdup("["), $3, mm_strdup("]"));
 	}
 ECPG: opt_array_bounds

src/interfaces/ecpg/preproc/ecpg.c

@@ -171,7 +171,7 @@ main(int argc, char *const argv[])
 				regression_mode = true;
 				break;
 			case 'o':
-				output_filename = strdup(optarg);
+				output_filename = mm_strdup(optarg);
 				if (strcmp(output_filename, "-") == 0)
 					yyout = stdout;
 				else
@@ -320,7 +320,7 @@ main(int argc, char *const argv[])
 					yyout = stdout;
 				else
 				{
-					output_filename = strdup(input_filename);
+					output_filename = mm_strdup(input_filename);
 
 					ptr2ext = strrchr(output_filename, '.');
 					/* make extension = .c resp. .h */

src/interfaces/ecpg/preproc/ecpg.trailer

@@ -1428,13 +1428,13 @@ action : CONTINUE_P
 		| SQL_GOTO name
 		{
 			$<action>$.code = W_GOTO;
-			$<action>$.command = strdup($2);
+			$<action>$.command = mm_strdup($2);
 			$<action>$.str = cat2_str(mm_strdup("goto "), $2);
 		}
 		| SQL_GO TO name
 		{
 			$<action>$.code = W_GOTO;
-			$<action>$.command = strdup($3);
+			$<action>$.command = mm_strdup($3);
 			$<action>$.str = cat2_str(mm_strdup("goto "), $3);
 		}
 		| DO name '(' c_args ')'