[SVE][Inline-Asm] Fix -Wimplicit-fallthrough in AArch64ISelLowering.cpp

Summary: Adds break to 'x' case in getRegForInlineAsmConstraint added by D66302, fixing the unintentional fallthrough.

Reviewers: sdesmalen, rovka, cameron.mcinally, greened, gribozavr, ruiu

Reviewed By: sdesmalen

Subscribers: bjope, javed.absar, tschuett, kristof.beyls, rkruppe, psnobl, llvm-commits, cfe-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67095

llvm-svn: 370769

llvm/lib/Target/AArch64/AArch64ISelLowering.cpp

@@ -5834,6 +5834,7 @@ AArch64TargetLowering::getRegForInlineAsmConstraint(
         return std::make_pair(0U, &AArch64::ZPR_4bRegClass);
       if (VT.getSizeInBits() == 128)
         return std::make_pair(0U, &AArch64::FPR128_loRegClass);
+      break;
     case 'y':
       if (!Subtarget->hasFPARMv8())
         break;