Fixed MacOS X build

git-svn-id: https://svn.pjsip.org/repos/pjproject/trunk@468 74dad513-b988-da41-8d7b-12977e46ad98
diff --git a/configure b/configure
index 408ef7f..0464a13 100755
--- a/configure
+++ b/configure
@@ -13,7 +13,7 @@
     MACHINE_NAME=i386
 elif echo $MACHINE | grep alpha > /dev/null; then
     MACHINE_NAME=alpha
-elif echo $MACHINE | grep powerpc > /dev/null; then
+elif echo $MACHINE | grep Mac > /dev/null; then
     MACHINE_NAME=powerpc
 else
     echo "Unable to detect processor type ('uname -m' == '$MACHINE')"