Get rid of /env/pgsz.

Reference: /n/patches.lsub.org/patch/nopgsz
Date: Tue Jul  3 11:01:32 CES 2012
Signed-off-by: nemo@lsub.org

--- /sys/src/nix/k10/main.c	Fri Jun 29 12:55:47 2012
+++ /sys/src/nix/k10/main.c	Tue Jul  3 10:08:20 2012
@@ -406,7 +406,6 @@
 			ksetenv("service", "cpu", 0);
 		else
 			ksetenv("service", "terminal", 0);
-		ksetenv("pgsz", "2097152", 0);
 		confsetenv();
 		poperror();
 	}