MAINTAINERS: update X86 machine entry

Add a bunch of files missing, and add self as maintainer.  Since I'm
hacking on these anyway, it will be helpful if people Cc me on patches.
Anthony gets to review everything anyway ...

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index 3e61ac8..e250d72 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -500,9 +500,23 @@
 ------------
 PC
 M: Anthony Liguori <aliguori@amazon.com>
+M: Michael S. Tsirkin <mst@redhat.com>
 S: Supported
-F: hw/i386/pc.[ch]
-F: hw/i386/pc_piix.c
+F: include/hw/i386/
+F: hw/i386/
+F: hw/pci-host/piix.c
+F: hw/pci-host/q35.c
+F: hw/pci-host/pam.c
+F: include/hw/pci-host/q35.h
+F: include/hw/pci-host/pam.h
+F: hw/isa/piix4.c
+F: hw/isa/lpc_ich9.c
+F: hw/i2c/smbus_ich9.c
+F: hw/acpi/piix4.c
+F: hw/acpi/ich9.c
+F: include/hw/acpi/ich9.h
+F: include/hw/acpi/piix.h
+
 
 Xtensa Machines
 ---------------