add M68kRTD to clang calling conventions

src/clang.zig

@@ -2107,6 +2107,7 @@ pub const CallingConv = enum(c_int) {
     AArch64VectorCall,
     AArch64SVEPCS,
     AMDGPUKernelCall,
+    M68kRTD,
 };
 
 pub const StorageClass = enum(c_int) {

src/zig_clang.cpp

@@ -2115,6 +2115,7 @@ void ZigClang_detect_enum_CallingConv(clang::CallingConv x) {
         case clang::CC_AArch64VectorCall:
         case clang::CC_AArch64SVEPCS:
         case clang::CC_AMDGPUKernelCall:
+        case clang::CC_M68kRTD:
             break;
     }
 }
@@ -2140,6 +2141,7 @@ static_assert((clang::CallingConv)ZigClangCallingConv_PreserveAll == clang::CC_P
 static_assert((clang::CallingConv)ZigClangCallingConv_AArch64VectorCall == clang::CC_AArch64VectorCall, "");
 static_assert((clang::CallingConv)ZigClangCallingConv_AArch64SVEPCS == clang::CC_AArch64SVEPCS, "");
 static_assert((clang::CallingConv)ZigClangCallingConv_AMDGPUKernelCall == clang::CC_AMDGPUKernelCall, "");
+static_assert((clang::CallingConv)ZigClangCallingConv_M68kRTD == clang::CC_M68kRTD, "");
 
 void ZigClang_detect_enum_StorageClass(clang::StorageClass x) {
     switch (x) {

src/zig_clang.h

@@ -1219,6 +1219,7 @@ enum ZigClangCallingConv {
     ZigClangCallingConv_AArch64VectorCall,
     ZigClangCallingConv_AArch64SVEPCS,
     ZigClangCallingConv_AMDGPUKernelCall,
+    ZigClangCallingConv_M68kRTD,
 };
 
 enum ZigClangStorageClass {