Refine wasm loader and interpreter, enhance wamrc to support SGX (#167)

Former-commit-id: 76f4a121d3c2a67114414fc60e80eba4bf49aa8e [formerly b1ab47945a40e6b249c9aa205d61281301585ea6]
Former-commit-id: 8e5c6e895eae22051a79a8d337a87cd2f431b6bc

core/shared/include/config.h

@@ -64,6 +64,10 @@ enum {
 #define WASM_ENABLE_JIT 0
 #endif
 
+#ifndef WASM_ENABLE_WAMR_COMPILER
+#define WASM_ENABLE_WAMR_COMPILER 0
+#endif
+
 #ifndef WASM_ENABLE_LIBC_BUILTIN
 #define WASM_ENABLE_LIBC_BUILTIN 0
 #endif

core/shared/platform/linux-sgx/bh_platform_log.c

@@ -8,18 +8,10 @@
 
 void bh_log_emit(const char *fmt, va_list ap)
 {
-   //TODO: stub impl
+    bh_vprintf_sgx(fmt, ap);
 }
 
-/*
-int bh_fprintf(FILE *stream, const char *fmt, ...)
-{
-   return 0;
-}
-*/
-
 int bh_fflush(void *stream)
 {
-    //TODO: stub impl
     return 0;
 }