tests/tcg: allow running tests for targets that don't have C compiler

Obviously there is better way to do this.

Signed-off-by: Alibek Omarov <a1ba.omarov@gmail.com>

configure

@@ -1866,7 +1866,8 @@ fi
 : ${cross_cc_sparc="$cross_cc_sparc64"}
 : ${cross_cc_cflags_sparc="-m32 -mcpu=supersparc"}
 : ${cross_cc_cflags_x86_64="-m64"}
-: ${cross_cc_e2k="e2k-linux-cc"}
+: ${cross_cc_e2k="e2k-linux-as"} # C compiler isn't public yet
+: ${cross_cc_e2k_ignore_checks="yes"}
 
 compute_target_variable() {
   if eval test -n "\"\${cross_prefix_$1}\""; then