[llvm] [AMDGPU][MC] Disable sendmsg SYSMSG_OP_HOST_TRAP_ACK on gfx9+ (PR #90203)

[Matt Arsenault via llvm-commits]

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@@ -1953,7 +1953,9 @@ bool isValidMsgOp(int64_t MsgId, int64_t OpId, const MCSubtargetInfo &STI,
     return 0 <= OpId && isUInt<OP_WIDTH_>(OpId);
 
   if (MsgId == ID_SYSMSG)
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arsenm wrote:

Braces 

https://github.com/llvm/llvm-project/pull/90203