* [posix] POSIX standard implementation for PSE51
- add some posix's interfaces that we haven't before.
- these PR have passed the interface definition test across gcc platfrom;
- have tested base on qemu-a9 and stm32h750-art-pi.
* [newlib] only enable POSIX.1-1990
* update projects
* [kernel][mem] Multiple instances of small memory allocation algorithm
* [kernel][mem] Change small memory management algorithm memory header flag
* [kernel][mem] Fix assertion problem
* [kernel][slab] Multiple instances of slab memory management algorithm
* [kernel][memheap] Remove rt_malloc/rt_free/rt_realloc and other related memory interfaces
* [kernel][mem] Clean up memory space of small memory management objects
* [kernel][kservice] Add memory application interface and thread protection interface
* [kernel][kservice] Fix function return value problem
* [kernel][memheap] Optimize memheaptrace print
* [kernel][memheap] Support best mode
* [kernel][memory] Remove semaphore lock
* [kernel][memheap] Add locked flag
* [kernel][memory] Support malloc memory in interrupt
* [kernel][memheap] Add 'memheapcheck' cmd
* [kernel][mem] Fix failure to request full memory
* [kernel][memheap] Fix compilation warning
* [kernel][mem] Fix mem realloc ASSERT
* [examples][testcases] Add small mem testcase
* [examples][mem_tc] Modify test memory size
* [examples][testcases] Add slab memory management algorithm test case
* [examples][testcases] fix small memory management algorithm test case
* [kernel][memory] Adjusting memory allocation algorithm object definition and interface
* [kernel][memory] Fix compilation warning
* [examples][utest] Fix mem test case
* [examples][utest] fix slab test case
* [utest][testcases] Shorten test time
* [kernel][memory] Formatting code
* [examples][utest] Adjust test run time
* [examples][utest] Formatting code
* [bsp] update all rtconfig.h
1. modify each dirver's INIT_EXPORT micro.
2. modify the lwip parameters' in rtconfig.h
3. insert keep section .rti_fn* in IAR link file
4. change part id from TM4C129XNCZAD to TM4C1294NCPDT
1. Add ETH MAC driver using DMA for Tx and Rx lwip pBuf.
2. Modify the tivaware emac library to fix the bug that PHY read is not stable when sysclk is 120MHz
3. In PHY IRQ handler, insert a dummy reading (REG_BMSR) before read PHY_STS to force update STS register.