perf pmu: Remove perf_pmu_lex() needless declaration

It builds without it, perhaps with some older combination of flex/bison
we needed this, clean it up a bit removing this.

Signed-off-by: Gaosheng Cui <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Athira Jajeev <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: James Clark <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Mark Rutland <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

tools/perf/util/pmu.y

@@ -10,8 +10,6 @@
 #include <string.h>
 #include "pmu.h"
 
-extern int perf_pmu_lex (void);
-
 #define ABORT_ON(val) \
 do { \
         if (val) \