winpthreads: Disable dll_dependency.S assembly on ARM64EC

Bootstrapping is not a concern with LLVM toolchains.

Signed-off-by: Jacek Caban <jacek@codeweavers.com>
diff --git a/mingw-w64-libraries/winpthreads/src/libgcc/dll_dependency.S b/mingw-w64-libraries/winpthreads/src/libgcc/dll_dependency.S
index 0496e94..21e1c89 100644
--- a/mingw-w64-libraries/winpthreads/src/libgcc/dll_dependency.S
+++ b/mingw-w64-libraries/winpthreads/src/libgcc/dll_dependency.S
@@ -1,5 +1,5 @@
 /* Implementation for gcc's internal stack-allocation routines.  */
-#if defined(__i386__) || defined(__x86_64__)
+#if defined(__i386__) || (defined(__x86_64__) && !defined(__arm64ec__))
 .global ___chkstk
 .global	__alloca