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/linux/pci_regs.h b/libc/kernel/uapi/linux/pci_regs.h
index 7b234f5..8122fbb 100644
--- a/libc/kernel/uapi/linux/pci_regs.h
+++ b/libc/kernel/uapi/linux/pci_regs.h
@@ -36,6 +36,7 @@
 #define PCI_COMMAND_FAST_BACK 0x200
 #define PCI_COMMAND_INTX_DISABLE 0x400
 #define PCI_STATUS 0x06
+#define PCI_STATUS_IMM_READY 0x01
 #define PCI_STATUS_INTERRUPT 0x08
 #define PCI_STATUS_CAP_LIST 0x10
 #define PCI_STATUS_66MHZ 0x20