perf env: Remove needless cpumap.h header

Only a 'struct perf_cmp_map' forward allocation is necessary, fix the
places that need the header but were getting it indirectly, by luck,
from env.h.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-3sj3n534zghxhk7ygzeaqlx9@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/tests/code-reading.c

@@ -19,7 +19,6 @@
 #include "evlist.h"
 #include "evsel.h"
 #include "thread_map.h"
-#include "cpumap.h"
 #include "machine.h"
 #include "map.h"
 #include "symbol.h"