Update to v5.18 kernel headers.

Kernel headers coming from:

Git: https://android.googlesource.com/kernel/common/
Branch: android-mainline
Tag: android-mainline-5.18

Test: Builds.
Test: All bionic unit tests pass on a coral device.
Change-Id: I5700813eec0fb0db55bee4d75b129400b7a239bd
diff --git a/libc/kernel/uapi/linux/rtc.h b/libc/kernel/uapi/linux/rtc.h
index cf5f22a..d75bc45 100644
--- a/libc/kernel/uapi/linux/rtc.h
+++ b/libc/kernel/uapi/linux/rtc.h
@@ -96,7 +96,8 @@
 #define RTC_FEATURE_UPDATE_INTERRUPT 4
 #define RTC_FEATURE_CORRECTION 5
 #define RTC_FEATURE_BACKUP_SWITCH_MODE 6
-#define RTC_FEATURE_CNT 7
+#define RTC_FEATURE_ALARM_WAKEUP_ONLY 7
+#define RTC_FEATURE_CNT 8
 #define RTC_PARAM_FEATURES 0
 #define RTC_PARAM_CORRECTION 1
 #define RTC_PARAM_BACKUP_SWITCH_MODE 2