Socket datagram

[DeathWish5]

improve socket code:
delete redundant parameter 'count'.
reorder socket signals.
run cargo fmt and clippy.

[coveralls]

Pull Request Test Coverage Report for Build 107321440

• 0 of 91 (0.0%) changed or added relevant lines in 2 files are covered.
• 6 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.08%) to 22.208%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
zircon-syscall/src/socket.rs	0	23	0.0%
zircon-object/src/ipc/socket.rs	0	68	0.0%

Files with Coverage Reduction	New Missed Lines	%
zircon-object/src/ipc/socket.rs	6	0%

Totals
Change from base Build 106305047:	-0.08%
Covered Lines:	1702
Relevant Lines:	7664

---

💛 - Coveralls

[wangrunji0408]

Emmm, no need to open a new PR. Just force-push to the PR branch.

[coveralls]

Pull Request Test Coverage Report for Build 107321440

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 91 (0.0%) changed or added relevant lines in 2 files are covered.
• 6 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.08%) to 22.208%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
zircon-syscall/src/socket.rs	0	23	0.0%
zircon-object/src/ipc/socket.rs	0	68	0.0%

Files with Coverage Reduction	New Missed Lines	%
zircon-object/src/ipc/socket.rs	6	0.0%

Totals
Change from base Build 106305047:	-0.08%
Covered Lines:	1702
Relevant Lines:	7664

---

💛 - Coveralls