Add target platform detection macros

Now we have arm/x86 32/64 detection

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/include/mbedtls/build_info.h b/include/mbedtls/build_info.h
index c0424da..1984813 100644
--- a/include/mbedtls/build_info.h
+++ b/include/mbedtls/build_info.h
@@ -49,6 +49,55 @@
 #define MBEDTLS_VERSION_STRING         "3.4.1"
 #define MBEDTLS_VERSION_STRING_FULL    "mbed TLS 3.4.1"
 
+/* Macros for build-time platform detection */
+
+#if !defined(MBEDTLS_ARCH_IS_ARM64) && \
+    (defined(__aarch64__) || defined(_M_ARM64) || defined(_M_ARM64EC))
+#define MBEDTLS_ARCH_IS_ARM64
+#endif
+
+#if !defined(MBEDTLS_ARCH_IS_ARM32) && \
+    (defined(__arm__) || defined(_M_ARM) || \
+    defined(_M_ARMT) || defined(__thumb__) || defined(__thumb2__))
+#define MBEDTLS_ARCH_IS_ARM32
+#endif
+
+#if !defined(MBEDTLS_ARCH_IS_X64) && \
+    (defined(__amd64__) || defined(__x86_64__) || \
+    ((defined(_M_X64) || defined(_M_AMD64)) && !defined(_M_ARM64EC)))
+#define MBEDTLS_ARCH_IS_X64
+#endif
+
+#if !defined(MBEDTLS_ARCH_IS_X86) && \
+    (defined(__i386__) || defined(_X86_) || \
+    (defined(_M_IX86) && !defined(_M_I86)))
+#define MBEDTLS_ARCH_IS_X86
+#endif
+/* Macros for build-time platform detection */
+
+#if !defined(MBEDTLS_ARCH_IS_ARM64) && \
+    (defined(__aarch64__) || defined(_M_ARM64) || defined(_M_ARM64EC))
+#define MBEDTLS_ARCH_IS_ARM64
+#endif
+
+#if !defined(MBEDTLS_ARCH_IS_ARM32) && \
+    (defined(__arm__) || defined(_M_ARM) || \
+    defined(_M_ARMT) || defined(__thumb__) || defined(__thumb2__))
+#define MBEDTLS_ARCH_IS_ARM32
+#endif
+
+#if !defined(MBEDTLS_ARCH_IS_X64) && \
+    (defined(__amd64__) || defined(__x86_64__) || \
+    ((defined(_M_X64) || defined(_M_AMD64)) && !defined(_M_ARM64EC)))
+#define MBEDTLS_ARCH_IS_X64
+#endif
+
+#if !defined(MBEDTLS_ARCH_IS_X86) && \
+    (defined(__i386__) || defined(_X86_) || \
+    (defined(_M_IX86) && !defined(_M_I86)))
+#define MBEDTLS_ARCH_IS_X86
+#endif
+
 #if defined(_MSC_VER) && !defined(_CRT_SECURE_NO_DEPRECATE)
 #define _CRT_SECURE_NO_DEPRECATE 1
 #endif