OpenBSD wants DIR_HAS_BSD_GROUP_SEMANTICS, just like FreeBSD

Index: config.mak.uname
--- config.mak.uname.orig
+++ config.mak.uname
@@ -270,8 +270,7 @@ ifeq ($(uname_S),OpenBSD)
 	ifeq ($(shell expr "$(uname_R)" : "[1-6]\."),2)
 		NO_UNCOMPRESS2 = UnfortunatelyYes
 	endif
-	NO_STRCASESTR = YesPlease
-	NO_MEMMEM = YesPlease
+	DIR_HAS_BSD_GROUP_SEMANTICS = YesPlease
 	USE_ST_TIMESPEC = YesPlease
 	NEEDS_LIBICONV = YesPlease
 	BASIC_CFLAGS += -I/usr/local/include
