Buflib_init Bugfix Minsize

when buflib_init is called with a buffer smaller than
sizeof(union buflib_data); size will be zero
Later when the alloc fails buflib will keep try to free items
in order to satisify the request this crashes in the sim
I suspect this behavior holds true on device as well
but I havent verified this as of yet.

patch adds minimal overhead to the buflib and panics when the size is too small

Change-Id: I46e510367fc1cac19ce01ee6f92d8cf0d65ef914

firmware/buflib.c

@@ -123,6 +123,12 @@ buflib_init(struct buflib_context *ctx, void *buf, size_t size)
      */
     ctx->alloc_end = bd_buf;
     ctx->compact = true;
+
+    if (size == 0)
+    {
+        BPANICF("buflib_init error (CTX:%p, %zd bytes):\n", ctx,
+            (ctx->handle_table - ctx->buf_start) * sizeof(union buflib_data));
+    }
 }
 
 bool buflib_context_relocate(struct buflib_context *ctx, void *buf)