[tools-v2] curvefs update fs failed to set fsname

[h0hmj]

Describe the bug (描述bug)
curve fs update fs --fsname fs1 --capacity 10GiB

failed to set fsname in request

To Reproduce (复现方法)

above

Expected behavior (期望行为)

should set fsname in request

root cause

command line parse "fsname"
when get and set request, use "fsName"

need fix