tools lib subcmd: Fix a few source code comment typos

Go over the tools/ files that are maintained in Arnaldo's tree and
fix common typos: half of them were in comments, the other half
in JSON files.

No change in functionality intended.

Committer notes:

This was split from a larger patch as there are code that is,
additionally, maintained outside the kernel tree, so to ease
cherry-picking and/or backporting, split this into multiple patches.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20181203102200.GA104797@gmail.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/subcmd/parse-options.h

@@ -71,7 +71,7 @@ typedef int parse_opt_cb(const struct option *, const char *arg, int unset);
  *
  * `argh`::
  *   token to explain the kind of argument this option wants. Keep it
- *   homogenous across the repository.
+ *   homogeneous across the repository.
  *
  * `help`::
  *   the short help associated to what the option does.
@@ -80,7 +80,7 @@ typedef int parse_opt_cb(const struct option *, const char *arg, int unset);
  *
  * `flags`::
  *   mask of parse_opt_option_flags.
- *   PARSE_OPT_OPTARG: says that the argument is optionnal (not for BOOLEANs)
+ *   PARSE_OPT_OPTARG: says that the argument is optional (not for BOOLEANs)
  *   PARSE_OPT_NOARG: says that this option takes no argument, for CALLBACKs
  *   PARSE_OPT_NONEG: says that this option cannot be negated
  *   PARSE_OPT_HIDDEN this option is skipped in the default usage, showed in