tools: resource-monitor: Keep the alignment of resource attribute name

tools: resource-monitor: Keep the alignment of resource attribute name

commit f59279ad7f63 ("resource: Change bytes unit attributes to kilo-bytes")
changed the attribute name of both PROCESS_GROUP_ATTR_DISK_READ_PER_SEC
and PROCESS_GROUP_ATTR_DISK_WRITE_PER_SEC. So that break the alignment
when print the resource attribute name by resource-monitor cli tool.

Extend the width length for resource attribute name to keep the printing
alignement.

- Before change:
 7: 2|         PROCESS_GROUP_ATTR_CPU_UTIL |                                     0.27 | %     | Process-group CPU utilization
 7: 3| PROCESS_GROUP_ATTR_DISK_READ_PER_SEC |                                     0.00 | kB/s  | Process-group disk read per second
 7: 4| PROCESS_GROUP_ATTR_DISK_WRITE_PER_SEC |                                     0.00 | kB/s  | Process-group disk write per second
 7: 5|         PROCESS_GROUP_ATTR_MEM_VIRT |                                132923188 | kB    | Process-group VIRT memory size

- After change:
 7: 2|              PROCESS_GROUP_ATTR_CPU_UTIL |                                     0.21 | %     | Process-group CPU utilization
 7: 3|     PROCESS_GROUP_ATTR_DISK_READ_PER_SEC |                                     0.00 | kB/s  | Process-group disk read per second
 7: 4|    PROCESS_GROUP_ATTR_DISK_WRITE_PER_SEC |                                     0.00 | kB/s  | Process-group disk write per second
 7: 5|              PROCESS_GROUP_ATTR_MEM_VIRT |                                135495517 | kB    | Process-group VIRT memory size

Change-Id: I62a937f1edb9c85979cd6f309b12e94256dbeaed
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>