allow spaces in the path to srcdir

taken from https://packages.debian.org/sid/ecl

$ cat harden-configure.patch 
Description: Make configure work even when the current directory contains spaces
Author: Christoph Egger <christoph@debian.org>
Forwarded: NA

--- ecl.orig/configure
+++ ecl/configure
@@ -10,7 +10,7 @@
 #else
 #  srcdir=`pwd`/src
 #fi
-srcdir=`pwd`/src
+srcdir="`pwd`/src"
 [ "x$buildir" = "x" ] && buildir=build
 export buildir
 
@@ -34,6 +34,6 @@
 fi
 
 cd ${buildir}
-${srcdir}/configure --srcdir=${srcdir} "$@"
+"${srcdir}/configure" --srcdir="${srcdir}" $*
 
 echo Configuration complete. To build ECL, issue 'make' in this directory.