Add port GCC_RISC_V_GENERIC and IAR_RISC_V_GENERIC

[chinglee-iot]

Description

In order not to break existing risc-v project with cmake, two new ports are created:

• GCC_RISC_V_GENERIC
• IAR_RISC_V_GENERIC

FREERTOS_CHIP_EXTENSION has to be specify when using these ports.

Test Steps

Create a RISC-V cmake project to use port GCC_RISC_V_GENERIC.
There will be error message If FREERTOS_RISCV_EXTENSION is not set or not supported.

cmake -S . -B build
-- The C compiler identification is GNU 10.2.0
-- The ASM compiler identification is GNU
-- Found assembler: /usr/bin/cc.exe
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /usr/bin/cc.exe - skipped
-- Detecting C compile features
-- Detecting C compile features - done
CMake Error at /home/chinglee/kernel/FreeRTOS/FreeRTOS/Source/portable/GCC/RISC-V/chip_extensions.cmake:9 (message):
  FREERTOS_RISCV_EXTENSION "RISCV_MTIMEaefae_CLINT_no_extensions" is not set
  or unsupported.

  Please specify it from top-level CMake file (example):

     set(FREERTOS_RISCV_EXTENSION RISCV_MTIME_CLINT_no_extensions CACHE STRING "")
   or from CMake command line option:
     -DFREERTOS_RISCV_EXTENSION=RISCV_MTIME_CLINT_no_extensions



   Available extension options:
     Pulpino_Vega_RV32M1RM;RISCV_MTIME_CLINT_no_extensions;RISCV_no_extensions;RV32I_CLINT_no_extensions

Call Stack (most recent call first):
  /home/chinglee/kernel/FreeRTOS/FreeRTOS/Source/portable/CMakeLists.txt:2 (include)


-- Configuring incomplete, errors occurred!
See also "/home/chinglee/kernel/FreeRTOS/FreeRTOS/Demo/RISC-V-Qemu-virt_GCC/build/CMakeFiles/CMakeOutput.log".

Checklist:

• I have tested my changes. No regression in existing tests.
• I have modified and/or added unit-tests to cover the code changes in this Pull Request.

Related Issue

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