[AMDGPU] Remove feature register-banking

Since RegBankReassign pass was removed this feature is not
use for anything.

Differential Revision: https://reviews.llvm.org/D118195

llvm/lib/Target/AMDGPU/AMDGPU.td

@@ -610,12 +610,6 @@ def FeatureDsSrc2Insts : SubtargetFeature<"ds-src2-insts",
   "Has ds_*_src2 instructions"
 >;
 
-def FeatureRegisterBanking : SubtargetFeature<"register-banking",
-  "HasRegisterBanking",
-  "true",
-  "Has register banking"
->;
-
 def FeatureVOP3Literal : SubtargetFeature<"vop3-literal",
   "HasVOP3Literal",
   "true",
@@ -826,7 +820,7 @@ def FeatureGFX10 : GCNSubtargetFeatureGeneration<"GFX10",
    FeatureSDWA, FeatureSDWAOmod, FeatureSDWAScalar, FeatureSDWASdst,
    FeatureFlatInstOffsets, FeatureFlatGlobalInsts, FeatureFlatScratchInsts,
    FeatureAddNoCarryInsts, FeatureFmaMixInsts, FeatureGFX8Insts,
-   FeatureNoSdstCMPX, FeatureVscnt, FeatureRegisterBanking,
+   FeatureNoSdstCMPX, FeatureVscnt,
    FeatureVOP3Literal, FeatureDPP8, FeatureExtendedImageInsts,
    FeatureNoDataDepHazard, FeaturePkFmacF16Inst,
    FeatureGFX10A16, FeatureSMemTimeInst, FeatureFastDenormalF32, FeatureG16,

llvm/lib/Target/AMDGPU/AMDGPUSubtarget.cpp

@@ -269,7 +269,6 @@ GCNSubtarget::GCNSubtarget(const Triple &TT, StringRef GPU, StringRef FS,
     HasGetWaveIdInst(false),
     HasSMemTimeInst(false),
     HasShaderCyclesRegister(false),
-    HasRegisterBanking(false),
     HasVOP3Literal(false),
     HasNoDataDepHazard(false),
     FlatAddressSpace(false),

llvm/lib/Target/AMDGPU/GCNSubtarget.h

@@ -153,7 +153,6 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
   bool HasGetWaveIdInst;
   bool HasSMemTimeInst;
   bool HasShaderCyclesRegister;
-  bool HasRegisterBanking;
   bool HasVOP3Literal;
   bool HasNoDataDepHazard;
   bool FlatAddressSpace;
@@ -723,10 +722,6 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
     return HasShaderCyclesRegister;
   }
 
-  bool hasRegisterBanking() const {
-    return HasRegisterBanking;
-  }
-
   bool hasVOP3Literal() const {
     return HasVOP3Literal;
   }