Update to v4.20.1 kernel headers.

This includes one manual change:

In the file bionic/libc/kernel/uapi/linux/in.h, the macro IN_BADCLASS
was not definied correctly. Change the macro from:

  #define IN_BADCLASS(a) ((((long int) (a)) == 0xffffffff)

to:

  #define IN_BADCLASS(a) (((long int) (a)) == (long int)0xffffffff)

This change is being pushed to the upstream kernels.

Test: Builds and boots.
Change-Id: Ia304773a9dc6789b34d9769d73742384d6afb571
Merged-In: Ia304773a9dc6789b34d9769d73742384d6afb571
(cherry picked from commit 967fb01cce73591281e7804e2c0fa9f83b618f5b)
diff --git a/libc/kernel/uapi/asm-x86/asm/bootparam.h b/libc/kernel/uapi/asm-x86/asm/bootparam.h
index b010277..dc90f57 100644
--- a/libc/kernel/uapi/asm-x86/asm/bootparam.h
+++ b/libc/kernel/uapi/asm-x86/asm/bootparam.h
@@ -135,7 +135,8 @@
   __u8 _pad2[4];
   __u64 tboot_addr;
   struct ist_info ist_info;
-  __u8 _pad3[16];
+  __u64 acpi_rsdp_addr;
+  __u8 _pad3[8];
   __u8 hd0_info[16];
   __u8 hd1_info[16];
   struct sys_desc_table sys_desc_table;