[RISCV] Remove unused Predicates. NFC

Author: topperc

llvm/lib/Target/RISCV/RISCVFeatures.td

@@ -179,7 +179,6 @@ def FeatureStdExtZicfiss
 def HasStdExtZicfiss : Predicate<"Subtarget->hasStdExtZicfiss()">,
                        AssemblerPredicate<(all_of FeatureStdExtZicfiss),
                                           "'Zicfiss' (Shadow stack)">;
-def NoHasStdExtZicfiss : Predicate<"!Subtarget->hasStdExtZicfiss()">;
 
 def FeatureStdExtZilsd
     : RISCVExtension<1, 0,
@@ -188,7 +187,6 @@ def FeatureStdExtZilsd
 def HasStdExtZilsd : Predicate<"Subtarget->hasStdExtZilsd()">,
                        AssemblerPredicate<(all_of FeatureStdExtZilsd),
                                           "'Zilsd' (Load/Store pair instructions)">;
-def NoHasStdExtZilsd : Predicate<"!Subtarget->hasStdExtZilsd()">;
 
 // Multiply Extensions