Merge branch '351-disable-cmocka-by-default-v9_12' into 'v9_12'

Resolve "configure fails unless --enable-developer is specified"

See merge request isc-projects/bind9!1019

configure

@@ -23168,7 +23168,9 @@ fi
 
 # Check whether --with-cmocka was given.
 if test "${with_cmocka+set}" = set; then :
-  withval=$with_cmocka;
+  withval=$with_cmocka; :
+else
+  with_cmocka=no
 fi
 
 

configure.ac

@@ -4793,7 +4793,8 @@ fi
 #
 
 AC_ARG_WITH([cmocka],
-	    [AS_HELP_STRING([--with-cmocka=no],[enable cmocka based tests (default is no)])])
+	    [AS_HELP_STRING([--with-cmocka=no],[enable cmocka based tests (default is no)])],
+	    [:],[with_cmocka=no])
 
 AS_CASE([$with_cmocka],
 	[no],[:],