[修改] 增加freeRTOS

1. 版本FreeRTOSv202212.01，命名为kernel；

kernel/FreeRTOS-Plus/Source/Utilities/backoff_algorithm/lexicon.txt

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+api
+apis
+aws
+backoff
+backoff
+backoffalgorithm
+backoffalgorithmretriesexhausted
+backoffalgorithmrngfailure
+backoffalgorithmsuccess
+backoffbase
+br
+colspan
+com
+copydoc
+defgroup
+dns
+endif
+fd
+freertos
+gcc
+getaddrinfo
+github
+html
+https
+ifdef
+ifndef
+inc
+ingroup
+iot
+iso
+longjmp
+mainpage
+maxattempts
+maxbackoff
+maxretryattempts
+md
+min
+misra
+mit
+mockrng
+noninfringement
+os
+param
+pcontext
+pnextbackoff
+posix
+pretrycontext
+pretryparams
+prng
+rand
+randomvalue
+readme
+rm
+rng
+sdk
+spdx
+shouldn
+stderr
+sublicense
+tcp
+td
+toolchain
+tr
+trng
+usleep