osd: Remove the generic "osd_mclock_max_capacity_iops" option.

osd: Remove the generic "osd_mclock_max_capacity_iops" option.

Remove the generic "osd_mclock_max_capacity_iops" option and use the
"osd_mclock_max_capacity_iops_[hdd,ssd]" options. It is better to have a
clear indication about the type of underlying device. This helps in
avoiding confusion when trying to read or override the options.

Signed-off-by: Sridhar Seshasayee <sseshasa@redhat.com>
(cherry picked from commit 6ad38a291dd1fffb5a8b9ad786dd7ca22f67f411)

Conflicts:
    src/common/options/osd.yaml.in
- Removed non-existent file: src/common/options/osd.yaml.in since the
  switch to yaml for config options is not available in pacific yet.
- Removed config option "osd_mclock_max_capacity_iops" from options.cc.