bpo-38527: fix configure script for Solaris (GH-16845)


On Solaris, the regular "grep" command may be an old version that fails to search a binary file. We need to use the correct command (ggrep, in our case), which is found by the configure script earlier.

Automerge-Triggered-By: @pablogsal
(cherry picked from commit 5dd836030e0e399b21ab0865ae0d93934bdb3930)

Co-authored-by: Arnon Yaari <wiggin15@yahoo.com>
diff --git a/configure b/configure
index 3dfd6cc..8886561 100755
--- a/configure
+++ b/configure
@@ -14303,10 +14303,10 @@
 if ac_fn_c_try_compile "$LINENO"; then :
 
 
-if grep noonsees conftest.$ac_objext >/dev/null ; then
+if $GREP noonsees conftest.$ac_objext >/dev/null ; then
   ax_cv_c_float_words_bigendian=yes
 fi
-if grep seesnoon conftest.$ac_objext >/dev/null ; then
+if $GREP seesnoon conftest.$ac_objext >/dev/null ; then
   if test "$ax_cv_c_float_words_bigendian" = unknown; then
     ax_cv_c_float_words_bigendian=no
   else