MFH: r543914 r544154 r544630 r545155

With these changes libX11 in 2020Q3 branch should be mostly up to date with
what's in the default ports tree branch.

This is needed because the amount of patches fixing various issues started to
pile up, and it was hard to merge the needed patches one by one.

x11/libX11: Update to 1.6.10

Update x11/libX11 to 1.6.10.
Changelog:
https://lists.x.org/archives/xorg-announce/2020-July/003052.html

PR: 248409
Submitted by: VVD

x11/libX11: Fix regression after security fixes

Add an upstream patch that fixes regressions after the last round of
security updates, and the update to 1.6.10.
This regression causes issues with emacs, at least.

Reported by: Kevin Oberman

x11/libX11: Update to 1.6.11

Update x11/libX11 to 1.6.11.
This is effectively a noop, since the only change between 1.6.10 and 1.6.11
has already been included in the port.
Bump the version anyway to keep things up to date.

x11/libX11: Fix regression with inputh methods

Add an upstream patch to fix regressions with input metods, where input
method clients can't connect to the input method server. [1]
While here, add a patch that removes register keywords and fixes compiles
against libX11 headers with C++17.

PR: 248549 [1]
Reported by: Atsuo Ohki

Approved by: ports-secteam (joenum)