[llvm] MC: Simplify fragment reuse determination (PR #149471)

[Fangrui Song via llvm-commits]

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@@ -9,6 +9,7 @@
 # CHECK-NEXT:0 Data LinkerRelaxable Size:8 [97,00,00,00,e7,80,00,00]
 # CHECK-NEXT:  Fixup @0 Value:specifier(19,ext) Kind:4023
 # CHECK-NEXT:  Symbol @0 $x
+# CHECK-NEXT:8 Data Size:0 []
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MaskRay wrote:

#149030 will remove this empty FT_Data. The fragment mechanism requires a large overhaul and I need to split the changes into pieces. The state after this patch does introduce an extra empty fragment for this corner case of RISC-V.

https://github.com/llvm/llvm-project/pull/149471