Update to v6.6 kernel headers.

Kernel headers coming from:

Git: https://android.googlesource.com/kernel/common/
Branch: android-mainline
Tag: android-mainline-6.6

Test: Builds and bionic unit tests pass on raven.
Test: Able to log in to an Android GO 32 bit device.
Change-Id: Ib5ff5a23f382721d98d1e428a295c6794b190d8d
diff --git a/libc/include/bits/glibc-syscalls.h b/libc/include/bits/glibc-syscalls.h
index 50817af..ccccf46 100644
--- a/libc/include/bits/glibc-syscalls.h
+++ b/libc/include/bits/glibc-syscalls.h
@@ -222,6 +222,9 @@
 #if defined(__NR_fchmodat)
   #define SYS_fchmodat __NR_fchmodat
 #endif
+#if defined(__NR_fchmodat2)
+  #define SYS_fchmodat2 __NR_fchmodat2
+#endif
 #if defined(__NR_fchown)
   #define SYS_fchown __NR_fchown
 #endif
@@ -573,6 +576,9 @@
 #if defined(__NR_madvise)
   #define SYS_madvise __NR_madvise
 #endif
+#if defined(__NR_map_shadow_stack)
+  #define SYS_map_shadow_stack __NR_map_shadow_stack
+#endif
 #if defined(__NR_mbind)
   #define SYS_mbind __NR_mbind
 #endif