perf inject: Remove unused 'input_name' static var

If we ever want to allow inject to work with something other than stdin,
we can put it back, but so far it is completely unused, so ditch it.

Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-qmwpnktckhd43eynnkxgqfpm@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/builtin-inject.c

@@ -14,7 +14,6 @@
 
 #include "util/parse-options.h"
 
-static char		const *input_name = "-";
 static bool		inject_build_ids;
 
 static int perf_event__repipe_synth(struct perf_tool *tool __maybe_unused,
@@ -245,7 +244,7 @@ static int __cmd_inject(void)
 		perf_inject.tracing_data = perf_event__repipe_tracing_data;
 	}
 
-	session = perf_session__new(input_name, O_RDONLY, false, true, &perf_inject);
+	session = perf_session__new("-", O_RDONLY, false, true, &perf_inject);
 	if (session == NULL)
 		return -ENOMEM;