add tos_mmheap_check & tos_mmheap_pool_check API and TOS_CFG_MMHEAP_DEFAULT_POOL_EN switch

tos_mmheap_check: get the information of the heap(space that is free and used)
tos_mmheap_pool_check: get the information of a pool
TOS_CFG_MMHEAP_DEFAULT_POOL_EN: enable the default pool of the heap(if user not set this, a default of 1u is set). if you wanna disable the default pool, you should call tos_mmheap_pool_add to add your own pool of the heap before tos_mmheap_alloc is called.

kernel/core/include/tos_err.h

@@ -47,6 +47,9 @@ typedef enum k_err_en {
 
     K_ERR_MMHEAP_INVALID_POOL_ADDR              = 800u,
     K_ERR_MMHEAP_INVALID_POOL_SIZE,
+    K_ERR_MMHEAP_POOL_OVERFLOW,
+    K_ERR_MMHEAP_POOL_ALREADY_EXIST,
+    K_ERR_MMHEAP_POOL_NOT_EXIST,
 
     K_ERR_MSG_QUEUE_FULL                        = 900u,
     K_ERR_MSG_QUEUE_EMPTY,