malloc_simple: Add logging of allocations

It is sometimes useful to see what memory is being allocated early during
boot. Add logging to support this, using a new LOGC_ALLOC category.

Signed-off-by: Simon Glass <sjg@chromium.org>

include/malloc.h

@@ -880,6 +880,7 @@ static inline void free(void *ptr) {}
 void *calloc(size_t nmemb, size_t size);
 void *memalign_simple(size_t alignment, size_t bytes);
 void *realloc_simple(void *ptr, size_t size);
+void malloc_simple_info(void);
 #else
 
 # ifdef USE_DL_PREFIX