perf events parse: Remove some needless local variables

perf events parse: Remove some needless local variables

Those are just casting a void pointer to a struct to then pass them to
functions, i.e. remove the local variables and pass the void pointer
directly, the casting will be done and the code will be shorter.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-bzfodzr3mb46gy7u7v0mqad6@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>