Fix generation of krb5-config with LC_CTYPE=*.UTF-8

When building on MacOS with a UTF-8 locale sed will fail when reading
krb-config.in due to invalid characters. Forcing the "C" locale fixes this.

Reviewed By:	emaste, cy
Differential Revision: https://reviews.freebsd.org/D16849

kerberos5/usr.bin/krb5-config/Makefile

@@ -5,8 +5,12 @@ MAN=	krb5-config.1
 
 CLEANFILES= krb5-config
 
+# In order for this to work on MacOS we need to set LC_ALL=C since the
+# krb5-config.in file contains characters that will be rejected by MacOS with
+# a UTF-8 locale (see https://stackoverflow.com/a/23584470/894271)
+# TODO: Should we just require LC_ALL=C during the build?
 krb5-config: krb5-config.in
-	sed -e "s,@PACKAGE@,FreeBSD heimdal,g" \
+	env LC_ALL=C sed -e "s,@PACKAGE@,FreeBSD heimdal,g" \
 	    -e "s,@VERSION@,1.1.0,g" \
 	    -e "s,@prefix@,/usr,g" \
 	    -e "s,@exec_prefix@,/usr,g" \