add an architecture name, since it is not clear on pc hardware which kernel might
be running.

Reference: /n/atom/patch/applied2013/fsarchname
Date: Wed Sep  4 18:46:30 CES 2013
Signed-off-by: quanstro@quanstro.net

--- /sys/src/fs/pc/archdat.h	Wed Sep  4 18:46:19 2013
+++ /sys/src/fs/pc/archdat.h	Wed Sep  4 18:46:19 2013
@@ -119,3 +119,4 @@
 
 #define		MACHP(n)	sys->machptr[n]
 #define		Ticks		sys->ticks
+#define		Archname	"386"
--- /sys/src/fs/amd64/archdat.h	Wed Sep  4 18:46:20 2013
+++ /sys/src/fs/amd64/archdat.h	Wed Sep  4 18:46:20 2013
@@ -195,3 +195,4 @@
 
 #define MACHP(n)	sys->machptr[n]
 #define Ticks		sys->ticks
+#define Archname	"amd64"