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/kernel/uapi/linux/elf.h b/libc/kernel/uapi/linux/elf.h
index 7eb29df..dc7cfbf 100644
--- a/libc/kernel/uapi/linux/elf.h
+++ b/libc/kernel/uapi/linux/elf.h
@@ -340,6 +340,7 @@
 #define NT_386_TLS 0x200
 #define NT_386_IOPERM 0x201
 #define NT_X86_XSTATE 0x202
+#define NT_X86_SHSTK 0x204
 #define NT_S390_HIGH_GPRS 0x300
 #define NT_S390_TIMER 0x301
 #define NT_S390_TODCMP 0x302
@@ -374,6 +375,8 @@
 #define NT_MIPS_DSP 0x800
 #define NT_MIPS_FP_MODE 0x801
 #define NT_MIPS_MSA 0x802
+#define NT_RISCV_CSR 0x900
+#define NT_RISCV_VECTOR 0x901
 #define NT_LOONGARCH_CPUCFG 0xa00
 #define NT_LOONGARCH_CSR 0xa01
 #define NT_LOONGARCH_LSX 0xa02