Turn on CLANG_IS_CC when not building gcc

[Dag-Erling Smørgrav]

The following patches (for head and stable/9) automatically enable
CLANG_IS_CC if GCC is disabled but CLANG is not.  Any objections?

Index: head/share/mk/bsd.own.mk
===================================================================
--- head/share/mk/bsd.own.mk	(revision 246325)
+++ head/share/mk/bsd.own.mk	(working copy)
@@ -526,6 +526,8 @@
 MK_CLANG_EXTRAS:= no
 MK_CLANG_FULL:= no
 MK_CLANG_IS_CC:= no
+.elif ${MK_GCC} == "no"
+MK_CLANG_IS_CC:= yes
 .endif
 
 #
Index: stable/9/share/mk/bsd.own.mk
===================================================================
--- stable/9/share/mk/bsd.own.mk	(revision 244989)
+++ stable/9/share/mk/bsd.own.mk	(working copy)
@@ -581,6 +581,8 @@
 
 .if ${MK_CLANG} == "no"
 MK_CLANG_IS_CC:= no
+.elif ${MK_GCC} == "no"
+MK_CLANG_IS_CC:= yes
 .endif
 
 MK_LIBCPLUSPLUS?= no

DES
-- 
Dag-Erling Smørgrav - des at des.no