Add Python support for hardware breakpoints

Add Python support for hardware breakpoints

This allows the creation of hardware breakpoints in Python with
gdb.Breakpoint(type=gdb.BP_HARDWARE_BREAKPOINT)
And they are included in the sequence returned by gdb.breakpoints().

gdb/ChangeLog:

2021-01-21  Hannes Domani  <ssbssa@yahoo.de>

	PR python/19151
	* python/py-breakpoint.c (bppy_get_location): Handle
	bp_hardware_breakpoint.
	(bppy_init): Likewise.
	(gdbpy_breakpoint_created): Likewise.

gdb/doc/ChangeLog:

2021-01-21  Hannes Domani  <ssbssa@yahoo.de>

	PR python/19151
	* python.texi (Breakpoints In Python): Document
	gdb.BP_HARDWARE_BREAKPOINT.

gdb/testsuite/ChangeLog:

2021-01-21  Hannes Domani  <ssbssa@yahoo.de>

	PR python/19151
	* gdb.python/py-breakpoint.exp: Add tests for hardware breakpoints.