build: separate compiler and libs

cl/_testrt/hello/in.go

@@ -1,10 +0,0 @@
-package main
-
-import "github.com/goplus/llgo/cl/internal/libc"
-
-var format = [...]int8{'H', 'e', 'l', 'l', 'o', ' ', '%', 'd', '\n', 0}
-
-func main() {
-	sfmt := &format[0]
-	libc.Printf(sfmt, libc.Strlen(sfmt))
-}