clang: Update compiler-provided C headers to Clang 19.

lib/include/module.modulemap

@@ -44,7 +44,6 @@ module _Builtin_intrinsics [system] [extern_c] {
     textual header "avxintrin.h"
     textual header "avx2intrin.h"
     textual header "avx512fintrin.h"
-    textual header "avx512erintrin.h"
     textual header "fmaintrin.h"
 
     header "x86intrin.h"
@@ -203,6 +202,11 @@ module _Builtin_stdarg [system] {
     export *
   }
 
+  explicit module header_macro {
+    header "__stdarg_header_macro.h"
+    export *
+  }
+
   explicit module va_arg {
     header "__stdarg_va_arg.h"
     export *
@@ -232,6 +236,10 @@ module _Builtin_stdbool [system] {
 module _Builtin_stddef [system] {
   textual header "stddef.h"
 
+  explicit module header_macro {
+    header "__stddef_header_macro.h"
+    export *
+  }
   // __stddef_max_align_t.h is always in this module, even if
   // -fbuiltin-headers-in-system-modules is passed.
   explicit module max_align_t {
@@ -315,3 +323,8 @@ module opencl_c {
   header "opencl-c.h"
   header "opencl-c-base.h"
 }
+
+module ptrauth {
+  header "ptrauth.h"
+  export *
+}