Fix compiler errors with JIT when Zbc is disabled

When using 'make ENABLE_Zbc=0 ENABLE_JIT=1', the following errors are
observed:

src/jit.c:1760:17: error: ‘do_clmulr’ defined but not used [-Werror=unused-function]
src/jit.c:1760:17: error: ‘do_clmulh’ defined but not used [-Werror=unused-function]
src/jit.c:1760:17: error: ‘do_clmul’ defined but not used [-Werror=unused-function]

Include 'Zbc' in EXT_LIST to ensure instructions like 'clmulr',
'clmulh', and 'clmul' are properly handled, resolving unused function
errors during JIT builds.

Author: eleanorLYJ

tools/gen-jit-template.py

@@ -127,8 +127,13 @@
         "orn",
         "andn",
     ],
+    "Zbc": [
+        "clmulr",
+        "clmulh",
+        "clmul",
+    ],
 }
-EXT_LIST = ["Zifencei", "Zicsr", "EXT_M", "EXT_A", "EXT_F", "EXT_C", "SYSTEM", "Zba", "Zbb"]
+EXT_LIST = ["Zifencei", "Zicsr", "EXT_M", "EXT_A", "EXT_F", "EXT_C", "SYSTEM", "Zba", "Zbb", "Zbc"]
 SKIP_LIST = []
 # check enabled extension in Makefile