Support 32bit iphb wakeup ranges

The changes are compatible with pre-existing 16 bit wakeup ranges both
in API and socket protocol levels.

Adds new function iphb_wait2() that allows
* using 32bit values for wakeup ranges
* synchronizing wakeups without forcing resume from suspend

The previously existing iphb_wait() is kept for API compatibility, but
is now just a wrapper for iphb_wait2().

[libiphb] Support 32bit iphb wakeup ranges. Contributes to JB#16116
Update hbtest3 to use the 32bit iphb wakeup ranges

Use iphb_wait2() instead of iphb_wait().

Add a wakeup that is far enough to need 32bit time spans and make the
test case fail if it gets triggered during the test execution.
Clarify why the request version field is set to one
Merge pull request #7 from spiiroin/32bit_iphb_ranges

Support 32bit iphb wakeup ranges
Use LGPLv2.1 license for hbtest3

The license was supposed to be the same as the other code has,
i.e. "LGPLv2.1". Due to copy paste error "LGPLv2" got applied.

[tests] Use LGPLv2.1 license for hbtest3
Set COPYING to GNU Lesser General Public License, version 2.1

Already in the initial commit every C and python source file refers to
LGPL v2.1. There is no code that refers to GPL.

Replaced existing COPYING file that contained GPL license with LGPL v2.1
license text retrieved from:
  https://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt

[libiphb] Set COPYING to GNU Lesser General Public License, version 2.1
Merge pull request #8 from spiiroin/licenses

Use LGPLv2.1