[RISCV] Avoid unnecessary stack align

[StephenFan]

Summary

The stack align is done in PEI's calculateFrameObjectOffsets method.
Here we don't need to do stack align again.

llvm/lib/Target/RISCV/RISCVFrameLowering.cpp

 // Determines the size of the frame and maximum call frame size.
 void RISCVFrameLowering::determineFrameLayout(MachineFunction &MF) const {
   MachineFrameInfo &MFI = MF.getFrameInfo();
   auto *RVFI = MF.getInfo<RISCVMachineFunctionInfo>();
 
   // Get the number of bytes to allocate from the FrameInfo.
   uint64_t FrameSize = MFI.getStackSize();
 
-  // Get the alignment.
-  Align StackAlign = getStackAlign();
-
-  // Make sure the frame is aligned.
-  FrameSize = alignTo(FrameSize, StackAlign);
-
-  // Update frame info.
-  MFI.setStackSize(FrameSize);
-
   // When using SP or BP to access stack objects, we may require extra padding
   // to ensure the bottom of the RVV stack is correctly aligned within the main
   // stack. We calculate this as the amount required to align the scalar local
   // variable section up to the RVV alignment.
   const TargetRegisterInfo *TRI = STI.getRegisterInfo();
   if (RVFI->getRVVStackSize() && (!hasFP(MF) || TRI->hasStackRealignment(MF))) {
     int ScalarLocalVarSize = FrameSize - RVFI->getCalleeSavedStackSize() -
                              RVFI->getVarArgsSaveSize();