[libc++abi][VE] Support VE in long double demangler

Support VE in long double demangler.  This patch corrects
libcxxabi/test/test_demangle.pass.cpp on VE.

Reviewed By: MaskRay, #libc_abi, ldionne

Differential Revision: https://reviews.llvm.org/D159004

Author: kaz7

libcxxabi/src/demangle/ItaniumDemangle.h

@@ -5134,7 +5134,8 @@ template <>
 struct FloatData<long double>
 {
 #if defined(__mips__) && defined(__mips_n64) || defined(__aarch64__) || \
-    defined(__wasm__) || defined(__riscv) || defined(__loongarch__)
+    defined(__wasm__) || defined(__riscv) || defined(__loongarch__) || \
+    defined(__ve__)
     static const size_t mangled_size = 32;
 #elif defined(__arm__) || defined(__mips__) || defined(__hexagon__)
     static const size_t mangled_size = 16;

llvm/include/llvm/Demangle/ItaniumDemangle.h

@@ -5129,7 +5129,8 @@ template <>
 struct FloatData<long double>
 {
 #if defined(__mips__) && defined(__mips_n64) || defined(__aarch64__) || \
-    defined(__wasm__) || defined(__riscv) || defined(__loongarch__)
+    defined(__wasm__) || defined(__riscv) || defined(__loongarch__) || \
+    defined(__ve__)
     static const size_t mangled_size = 32;
 #elif defined(__arm__) || defined(__mips__) || defined(__hexagon__)
     static const size_t mangled_size = 16;