blake3: fix Windows ARM64 build and detect ARM64EC as ARM64

Cherry-picked upstream 0816badf3ada3ec48e712dd4f4cbc2cd60828278

Reviewed-by: David Heidelberg <david@ixit.cz>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/29971>

src/util/blake3/blake3_dispatch.c

@@ -4,9 +4,12 @@
 
 #include "blake3_impl.h"
 
-#if defined(IS_X86)
 #if defined(_MSC_VER)
 #include <Windows.h>
+#endif
+
+#if defined(IS_X86)
+#if defined(_MSC_VER)
 #include <intrin.h>
 #elif defined(__GNUC__)
 #include <immintrin.h>

src/util/blake3/blake3_impl.h

@@ -28,7 +28,7 @@ enum blake3_flags {
 #define INLINE static inline __attribute__((always_inline))
 #endif
 
-#if defined(__x86_64__) || defined(_M_X64) 
+#if defined(__x86_64__) || defined(_M_X64) && !defined(_M_ARM64EC)
 #define IS_X86
 #define IS_X86_64
 #endif
@@ -38,7 +38,7 @@ enum blake3_flags {
 #define IS_X86_32
 #endif
 
-#if defined(__aarch64__) || defined(_M_ARM64)
+#if defined(__aarch64__) || defined(_M_ARM64)|| defined(_M_ARM64EC)
 #define IS_AARCH64
 #endif