Until now this feature has existed but was not documented. Adding docs
and tests.
gdb/ChangeLog:
yyyy-mm-dd Stafford Horne <shorne@gmail.com>
* infcmd.c (_initialize_infcmd): Add help for info reg $reggroup
and info all-registers $reggroup feature.
gdb/doc/ChangeLog:
yyyy-mm-dd Stafford Horne <shorne@gmail.com>
* gdb.texinfo (Registers): Document info reg $reggroup feature.
gdb/testsuite/ChangeLog:
yyyy-mm-dd Stafford Horne <shorne@gmail.com>
* gdb.base/reggroups.c: New file.
* gdb.base/reggroups.exp: New file.