8294087: RISC-V: RVC: Fix a potential alignment issue and add more alignment assertions for the patchable calls/nops

Reviewed-by: shade, fjiang, fyang

src/hotspot/cpu/riscv/macroAssembler_riscv.cpp

@@ -2828,6 +2828,11 @@ address MacroAssembler::trampoline_call(Address entry) {
   }
 
   address call_pc = pc();
+#ifdef ASSERT
+  if (entry.rspec().type() != relocInfo::runtime_call_type) {
+    assert_alignment(call_pc);
+  }
+#endif
   relocate(entry.rspec());
   if (!far_branches()) {
     jal(entry.target());