Fix bug #65088 (Generated configure script is malformed on OpenBSD).

We fell foul of a "common urban legend"[0], which resulted in us backslash
escaping double quotes that we didn't need to in acinclude.m4. This worked fine
on most shells, but OpenBSD's ksh implementation really didn't like it.

[0] http://www.gnu.org/savannah-checkouts/gnu/autoconf/manual/autoconf-2.69/html_node/Shell-Substitutions.html

NEWS

@@ -2,6 +2,10 @@ PHP                                                                        NEWS
 |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
 ?? ??? 2013, PHP 5.4.18
 
+- Core:
+  . Fixed bug #65088 (Generated configure script is malformed on OpenBSD).
+    (Adam)
+
 - CLI server:
   . Fixed bug #65066 (Cli server not responsive when responding with 422 http
     status code). (Adam)

acinclude.m4

@@ -66,10 +66,10 @@ AC_DEFUN([PHP_EXPAND_PATH],[
     $2=$1
   else
     changequote({,})
-    ep_dir="`echo $1|$SED 's%/*[^/][^/]*/*$%%'`"
+    ep_dir=`echo $1|$SED 's%/*[^/][^/]*/*$%%'`
     changequote([,])
-    ep_realdir="`(cd \"$ep_dir\" && pwd)`"
-    $2="$ep_realdir/`basename \"$1\"`"
+    ep_realdir=`(cd "$ep_dir" && pwd)`
+    $2="$ep_realdir"/`basename "$1"`
   fi
 ])