add DEBUGASSERT_MM_FREE_NODE macro

[ewoodev]

commit 1

mm/mm_heap: add mm_dump_heap_free_node_list function

add mm_dump_heap_free_node_list function.
This function prints the hex valuse contents of heap free nodes using heap free node list.

example logs:

` #########################################################################################
  Dump heap free node list
  [ndx], [HEAD]: [FREE NODES(SIZE)]
` #########################################################################################
    0, 1003dc80:
    1, 1003dc98:
    2, 1003dcb0:
    3, 1003dcc8: 0200f220(240)
    4, 1003dce0:
    5, 1003dcf8: 02012dc0(592) 02016b70(576)
    6, 1003dd10: 0201eb70(1488)
    7, 1003dd28:
    8, 1003dd40:
    9, 1003dd58:
   10, 1003dd70:
   11, 1003dd88:
   12, 1003dda0:
   13, 1003ddb8:
   14, 1003ddd0:
   15, 1003dde8:
   16, 1003de00: 02201a10(1828320)
   17, 1003de18:
   18, 1003de30:
`  #########################################################################################

commit 2

mm/mm_heap: move dump_node to mm_dump_node

add the dump_node function, which was static, to the header for use in other codes and move it to mm_heap_dbg.c

commit 3

mm/mm_heap/mm_node.h: add DEBUGASSERT_MM_FREE_NODE macro

The back link of heap free node cannot be null at any time, If null, it is an assert situation.
Therefore, in the REMOVE_NODE_FROM_LIST macro, null is checked with DEBUGASSERT.
But we can't known why the back link of the free node became null.

Therefore, This commit adds DEBUGASSERT_MM_FREE_NODE macro, that print addresses of free nodes, head
list of free node link and corrupted node nearby node for debugging.

[jeongarmy]

DEBUGPANIC() is a macro for up_assert function and up_assert sets abort_mode to true internally. Is it necessary?

[ewoodev]

#if defined(CONFIG_BUILD_FLAT) || defined(__KERNEL__)
#define mfdbg(format, ...)						\
	do {								\
		if (!IS_SECURE_STATE()) {				\
			if (abort_mode || up_interrupt_context()) {	\
				lldbg(format, ##__VA_ARGS__);		\
			} else {					\
				dbg(format, ##__VA_ARGS__);		\
			}						\
		}							\
	} while (0)
#else
#define mfdbg(format, ...) dbg(format, ##__VA_ARGS__)
#endif

TizenRT/os/include/debug.h

Line 504 in 4cced9a

#define mfdbg(format, ...) \

mfdbg operation has dependency with abort_mode.

if after print mfdbg( using dbg), up_assert is called, dbg can't finsh printing.
becase uart driver and lib stdout buffer is stop and print only using lldbg.

So, To complete print just before up_assert, abort mode setting is needed.

[ewoodev]

In fact.., This issue is not solved by setting abort_mode early about loadable user heap.. .
So, I'm checking to add lib stdout flush at up_assert.c

[jeongarmy]

Do you have any reasons to separate DEBUGASSERT_MM_NODE according to build type? I think both are same except setting of abort_mode. If it is not necessary as I said in below comment, we don't need to separate them.