Update to v6.0 kernel headers.

Kernel headers coming from:

Git: https://android.googlesource.com/kernel/common/
Branch: android-mainline
Tag: android-mainline-6.0

Test: Boots on coral.
Test: Bionic unit tests pass.
Change-Id: I282de83f23b432bef58214108a93700bdadddf0f
diff --git a/libc/kernel/uapi/linux/mmc/ioctl.h b/libc/kernel/uapi/linux/mmc/ioctl.h
index afea6a5..451134b 100644
--- a/libc/kernel/uapi/linux/mmc/ioctl.h
+++ b/libc/kernel/uapi/linux/mmc/ioctl.h
@@ -39,7 +39,7 @@
 #define mmc_ioc_cmd_set_data(ic,ptr) ic.data_ptr = (__u64) (unsigned long) ptr
 struct mmc_ioc_multi_cmd {
   __u64 num_of_cmds;
-  struct mmc_ioc_cmd cmds[0];
+  struct mmc_ioc_cmd cmds[];
 };
 #define MMC_IOC_CMD _IOWR(MMC_BLOCK_MAJOR, 0, struct mmc_ioc_cmd)
 #define MMC_IOC_MULTI_CMD _IOWR(MMC_BLOCK_MAJOR, 1, struct mmc_ioc_multi_cmd)