REGTEST: adapt some reg tests after renaming.

Some reg tests and their dependencies have been renamed. They may be
referenced by the .vtc files. So, this patch modifies also the references
to these dependencies.
diff --git a/reg-tests/http-rules/map_regm_with_backref.vtc b/reg-tests/http-rules/map_regm_with_backref.vtc
index 8fd39f7..502e8d3 100644
--- a/reg-tests/http-rules/map_regm_with_backref.vtc
+++ b/reg-tests/http-rules/map_regm_with_backref.vtc
@@ -57,9 +57,9 @@
     # Store host header in variable
     http-request set-var(txn.host) req.hdr(Host)
     # This works correctly
-    http-request set-header X-Mapped-From-Header %[req.hdr(Host),map_regm(${testdir}/b00000.map,"unknown")]
+    http-request set-header X-Mapped-From-Header %[req.hdr(Host),map_regm(${testdir}/map_regm_with_backref.map,"unknown")]
     # This breaks before commit 271022150d7961b9aa39dbfd88e0c6a4bc48c3ee
-    http-request set-header X-Mapped-From-Var %[var(txn.host),map_regm(${testdir}/b00000.map,"unknown")]
+    http-request set-header X-Mapped-From-Var %[var(txn.host),map_regm(${testdir}/map_regm_with_backref.map,"unknown")]
 
     default_backend be1