erlang: migrate BIFs onto registry, delete cond dispatchers (600/600)

lib/erlang/tests/runtime.sx

@@ -211,6 +211,11 @@
 (er-rt-test "reset clears" (len (er-list-bifs)) 0)
 (er-rt-test "reset lookup nil" (er-lookup-bif "fake" "echo" 1) nil)
 
+;; Re-populate built-in BIFs so subsequent test files (ring, ping-pong, etc.)
+;; can call length/spawn/etc. The migration onto the registry means a reset
+;; here would otherwise break the rest of the conformance suite.
+(er-register-builtin-bifs!)
+
 
 (define
   er-rt-test-summary