dyndbg: accept query terms like file=bar and module=foo

Current code expects "keyword" "arg" as 2 words, space separated.
Change to also accept "keyword=arg" form as well, and drop !(nwords%2)
requirement.  Then in rest of function, use new keyword, arg variables
instead of word[i], word[i+1]

Acked-by:  <jbaron@akamai.com>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20200719231058.1586423-15-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>