Add RISC-V architectures

docs/source/keywords.rst

@@ -487,14 +487,33 @@ If cross-compiling, or if you want to be specific, the CPU architecture can be p
     * - ``Kokkos_ARCH_KNL``
       - Knights Landing/x86-64
       - 31S1P @ Tianhe-2
-
     * - ``Kokkos_ARCH_KNC``
       - Knights Corner/x86-64
       -
 
     * - ``Kokkos_ARCH_SNB``
       - Sandy Bridge/x86-64
       -
+
+ .. list-table:: RISC-V CPU architectures
+    :widths: 30 30 30
+    :header-rows: 1
+    :align: left
+
+    * - CMake keyword
+      - Architecture/Instruction set
+      - Examples 
+      - Notes
+
+    * - ``KOKKOS_ARCH_RISCV_RVA22V``
+      -  RVA22V/RISC-V ISA
+      -
+      - (since Kokkos 4.5.0)
+
+    * - ``KOKKOS_ARCH_RISCV_SG2042``
+      -  SG2042/RISC-V ISA
+      -  
+      - (since Kokkos 4.3.0)
 
 GPU Architectures
 -----------------