Make WITHOUT_UNDEFINED_VERSION the default

Link with --no-undefined-version by default.  Will detect and prevent
the accidental removal of symbols from versioned libraries.

Reviewed by:	arichardson, kib, dim, emaste
Differential Revision:	https://reviews.freebsd.org/D44216

share/mk/bsd.opts.mk

@@ -68,7 +68,6 @@ __DEFAULT_YES_OPTIONS = \
     SSP \
     TESTS \
     TOOLCHAIN \
-    UNDEFINED_VERSION \
     WARNS \
     WERROR
 
@@ -81,7 +80,8 @@ __DEFAULT_NO_OPTIONS = \
     PROFILE \
     RETPOLINE \
     STALE_STAGED \
-    UBSAN
+    UBSAN \
+    UNDEFINED_VERSION
 
 __DEFAULT_DEPENDENT_OPTIONS = \
     MAKE_CHECK_USE_SANDBOX/TESTS \