linux: use correct libgcrypt-config paths when cross-compiling

linux: use correct libgcrypt-config paths when cross-compiling

Add a wrapper around libgcrypt-config to generate correct include and
library paths when cross-compiling using a sysroot.

BUG= Linux build with sysroot will fail
TEST= Build Linux Chromium for MIPS

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=258293

[petarj, 2014-03-19 16:57:45]

After the recent CL [1] that started to treat linker warnings as errors
on all POSIX platforms, link issue with libgcrypt paths came up.
This change fixes it.

Issue was spotted on a buildbot [2] that builds Linux Chromium for MIPS.

[1] Treat linker warnings as errors - CL,
https://codereview.chromium.org/196943020/
[2] MIPS buildbot -
http://www.rt-rk.com/mips-buildbot/builders/build_and_test_chromium_trunk_for...

[brettw, 2014-03-19 22:04:35]

I defer my review to piman, who understands this chroot stuff more than I.

[piman, 2014-03-20 08:18:13]

lgtm

[petarj, 2014-03-20 08:33:11]

The CQ bit was checked by petarj@mips.com

[commit-bot: I haz the power, 2014-03-20 08:33:22]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/petarj@mips.com/204553003/1

[commit-bot: I haz the power, 2014-03-20 09:05:32]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-03-20 09:05:33]

Try jobs failed on following builders:
  tryserver.chromium on mac_chromium_rel

[petarj, 2014-03-20 09:53:57]

The CQ bit was checked by petarj@mips.com

[commit-bot: I haz the power, 2014-03-20 09:54:12]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/petarj@mips.com/204553003/1

[commit-bot: I haz the power, 2014-03-20 14:53:37]

Change committed as 258293