Fixing a typo in a message from pkg_add -v

[Anthony Mallet <anthony.mallet%laas.fr@localhost>]

Hi,

I've just noticed this typo in the message printed by pkg_add -v, when it runs
the +INSTALL script. I guess it's trivial enough to not deserve a PR, does it? 
:)

Best,
Anthony

--- pkgtools/pkg_install/files/add/perform.c    2012-04-29 18:23:51.000000000 
+0200
+++ pkgtools/pkg_install/files/add/perform.c    2012-11-07 22:16:47.000000000 
+0100
@@ -980,7 +980,7 @@
        setenv(PKG_REFCOUNT_DBDIR_VNAME, config_pkg_refcount_dbdir, 1);
 
        if (Verbose)
-               printf("Running install with PRE-INSTALL for %s.\n", 
pkg->pkgname);
+               printf("Running install with %s for %s.\n", argument, 
pkg->pkgname);
        if (Fake)
                return 0;