patch from Andrew W. Nosenko, use se $GCC = 'yes' instead of $CC = 'gcc'

* configure.in: patch from Andrew W. Nosenko, use se $GCC = 'yes'
  instead of $CC = 'gcc' because GCC may have a different name
Daniel
diff --git a/configure.in b/configure.in
index 915f0ef..a608d05 100644
--- a/configure.in
+++ b/configure.in
@@ -752,7 +752,7 @@
 	    with_docbook="yes"
 	fi
     fi
-    if test "${CC}" = "gcc" ; then
+    if test "${GCC}" = "yes" ; then
     CFLAGS="-g -O -pedantic -W -Wformat -Wunused -Wimplicit -Wreturn-type -Wswitch -Wcomment -Wtrigraphs -Wformat -Wchar-subscripts -Wuninitialized -Wparentheses -Wshadow -Wpointer-arith -Wcast-align -Wwrite-strings -Waggregate-return -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Winline -Wredundant-decls -Wall"
     fi
     STATIC_BINARIES="-static"
@@ -812,7 +812,7 @@
 	   THREAD_CFLAGS="$THREAD_CFLAGS -DHAVE_BEOS_THREADS"
        ;;
        *linux*)
-           if test "${CC}" = "gcc" -a "${THREAD_LIBS}" = "-lpthread" ; then
+           if test "${GCC}" = "yes" -a "${THREAD_LIBS}" = "-lpthread" ; then
 	       THREAD_LIBS=""
 	       BASE_THREAD_LIBS="-lpthread"
 	   fi