New gdbarch functions: dtrace_parse_probe_argument, dtrace_probe_is_enabled, dtrace_e...

New gdbarch functions: dtrace_parse_probe_argument, dtrace_probe_is_enabled, dtrace_enable_probe, dtrace_disable_probe.

This patch adds several gdbarch functions (along with the corresponding
predicates): `dtrace_parse_probe_argument', `dtrace_probe_is_enabled',
`dtrace_enable_probe' and `dtrace_disable_probe'.  These functions will
be implemented by target-specific code, and called from the DTrace
probes implementation in order to calculate the value of probe
arguments, and manipulate is-enabled probes.

gdb/ChangeLog:

2015-02-17  Jose E. Marchesi  <jose.marchesi@oracle.com>

	* gdbarch.sh (dtrace_parse_probe_argument): New.
	(dtrace_probe_is_enabled): Likewise.
	(dtrace_enable_probe): Likewise.
	(dtrace_disable_probe): Likewise.
	* gdbarch.c: Regenerate.
	* gdbarch.h: Regenerate.