Fix compilation of Mac OS X. Without the cdecl modifier we need the _

rtl/bsd/system.pp:
  * use _PASCALMAIN instead of PASCALMAIN

git-svn-id: trunk@33034 -

rtl/bsd/system.pp

@@ -296,7 +296,7 @@ end;
 
 {$ifdef Darwin}
 
-procedure pascalmain;external name 'PASCALMAIN';
+procedure pascalmain;external name '_PASCALMAIN';
 
 procedure FPC_SYSTEMMAIN(argcparam: Longint; argvparam: ppchar; envpparam: ppchar); cdecl; [public];