Issue #12326: woops, I really mean 'linux', not 'linux2'

Copy/paste (from Python 3.2) failure
diff --git a/configure.in b/configure.in
index ec390e5..c10f67a 100644
--- a/configure.in
+++ b/configure.in
@@ -304,7 +304,7 @@
 	MACHDEP="$ac_md_system$ac_md_release"
 
 	case $MACHDEP in
-	linux*) MACHDEP="linux2";;
+	linux*) MACHDEP="linux";;
 	cygwin*) MACHDEP="cygwin";;
 	darwin*) MACHDEP="darwin";;
         irix646) MACHDEP="irix6";;