configure: Silence error when krb5-config is missing.

configure

@@ -13753,13 +13753,13 @@ then
   KRB5_CFLAGS=`$PKG_CONFIG --cflags krb5 2>/dev/null`
 fi
 fi
-test "$cross_compiling" = yes || KRB5_CFLAGS=${KRB5_CFLAGS:-`krb5-config --cflags`}
+test "$cross_compiling" = yes || KRB5_CFLAGS=${KRB5_CFLAGS:-`${KRB5_CONFIG:-krb5-config} --cflags 2>/dev/null`}
 if ${KRB5_LIBS:+false} :; then :
   if ${PKG_CONFIG+:} false; then :
   KRB5_LIBS=`$PKG_CONFIG --libs krb5 2>/dev/null`
 fi
 fi
-test "$cross_compiling" = yes || KRB5_LIBS=${KRB5_LIBS:-`krb5-config --libs`}
+test "$cross_compiling" = yes || KRB5_LIBS=${KRB5_LIBS:-`${KRB5_CONFIG:-krb5-config} --libs 2>/dev/null`}
 
 $as_echo "$as_me:${as_lineno-$LINENO}: krb5 cflags: $KRB5_CFLAGS" >&5
 $as_echo "$as_me:${as_lineno-$LINENO}: krb5 libs: $KRB5_LIBS" >&5

configure.ac

@@ -1629,7 +1629,9 @@ WINE_NOTICE_WITH(gsm,[test "x$ac_cv_lib_soname_gsm" = "x"],
 dnl **** Check for krb5 ****
 if test "x$with_krb5" != "xno"
 then
-    WINE_PACKAGE_FLAGS(KRB5,[krb5],,[`krb5-config --cflags`],[`krb5-config --libs`],
+    WINE_PACKAGE_FLAGS(KRB5,[krb5],,
+                       [`${KRB5_CONFIG:-krb5-config} --cflags 2>/dev/null`],
+                       [`${KRB5_CONFIG:-krb5-config} --libs 2>/dev/null`],
         [AC_CHECK_HEADERS([krb5/krb5.h])
          if test "$ac_cv_header_krb5_krb5_h" = "yes"
          then