Adjust oslc-err-initlist-return to function-redefinition warning on master.

Author: marsupial

testsuite/oslc-err-initlist-return/ref/out.txt

@@ -1,5 +1,6 @@
 test.osl:13: error: Cannot construct unknown (int, int, int)
 test.osl:13: error: Cannot return a 'unknown' from 'struct bcolor badreturn()'
+test.osl:14: warning: Function 'struct bcolor badreturn ()' declared twice in the same scope
 test.osl:14: error: Cannot return a 'struct acolor' from 'struct bcolor badreturn()'
 test.osl:17: error: Syntax error: syntax error
 FAILED test.osl