Update to android-mainline kernel headers v5.4.

Update generate_uapi_headers.sh to checkout the android mainline
kernel. Also, add a small modification to look for the kernel directory
in common not linux-stable.

Remove deprecated android headers from android/uapi/linux. Also,
remove f_accessory.h since it's in the android mainline kernel.

Test: Builds and runs on walleye.
Change-Id: Ia371305e19f56e6bcc2db6d5b4d299819f07ffc6
diff --git a/libc/kernel/uapi/scsi/scsi_netlink_fc.h b/libc/kernel/uapi/scsi/scsi_netlink_fc.h
index 9b374c7..ff92877 100644
--- a/libc/kernel/uapi/scsi/scsi_netlink_fc.h
+++ b/libc/kernel/uapi/scsi/scsi_netlink_fc.h
@@ -18,17 +18,18 @@
  ****************************************************************************/
 #ifndef SCSI_NETLINK_FC_H
 #define SCSI_NETLINK_FC_H
+#include <linux/types.h>
 #include <scsi/scsi_netlink.h>
 #define FC_NL_ASYNC_EVENT 0x0100
 #define FC_NL_MSGALIGN(len) (((len) + 7) & ~7)
 struct fc_nl_event {
   struct scsi_nl_hdr snlh;
-  uint64_t seconds;
-  uint64_t vendor_id;
-  uint16_t host_no;
-  uint16_t event_datalen;
-  uint32_t event_num;
-  uint32_t event_code;
-  uint32_t event_data;
-} __attribute__((aligned(sizeof(uint64_t))));
+  __u64 seconds;
+  __u64 vendor_id;
+  __u16 host_no;
+  __u16 event_datalen;
+  __u32 event_num;
+  __u32 event_code;
+  __u32 event_data;
+} __attribute__((aligned(sizeof(__u64))));
 #endif