Add myself as maintainer for chromebook-x86

This is currently the only x86 board.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/boards.cfg b/boards.cfg
index d31bdba..440c312 100644
--- a/boards.cfg
+++ b/boards.cfg
@@ -1217,7 +1217,7 @@
 Active  sparc       leon3          -           gaisler         -                   gr_ep2s60                             -                                                                                                                                 -
 Active  sparc       leon3          -           gaisler         -                   gr_xc3s_1500                          -                                                                                                                                 -
 Active  sparc       leon3          -           gaisler         -                   grsim                                 -                                                                                                                                 -
-Active  x86         x86            coreboot    chromebook-x86  coreboot            coreboot-x86                          coreboot:SYS_TEXT_BASE=0x01110000                                                                                                 -
+Active  x86         x86            coreboot    chromebook-x86  coreboot            coreboot-x86                          coreboot:SYS_TEXT_BASE=0x01110000                                                                                                 Simon Glass <sjg@chromium.org>
 # The following were moved to "Orphan" in April, 2014
 Orphan  powerpc     74xx_7xx       -           -               evb64260            ZUMA                                  -                                                                                                                                 Nye Liu <nyet@zumanetworks.com>
 Orphan  powerpc     mpc824x        -           -               musenki             MUSENKI                               -                                                                                                                                 Jim Thompson <jim@musenki.com>