target/riscv: Add a TYPE_RISCV_CPU_BASE CPU

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Bin Meng <bin.meng@windriver.com>
Tested-by: Bin Meng <bin.meng@windriver.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Acked-by: Palmer Dabbelt <palmerdabbelt@google.com>
Message-id: 86e5ccd9eae2f5d8c2257679c6ccf6078a5d51af.1608142916.git.alistair.francis@wdc.com

target/riscv/cpu.h

@@ -44,6 +44,12 @@
 #define TYPE_RISCV_CPU_SIFIVE_U34       RISCV_CPU_TYPE_NAME("sifive-u34")
 #define TYPE_RISCV_CPU_SIFIVE_U54       RISCV_CPU_TYPE_NAME("sifive-u54")
 
+#if defined(TARGET_RISCV32)
+# define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE32
+#elif defined(TARGET_RISCV64)
+# define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE64
+#endif
+
 #define RV32 ((target_ulong)1 << (TARGET_LONG_BITS - 2))
 #define RV64 ((target_ulong)2 << (TARGET_LONG_BITS - 2))