fix func kcl_alloc.

[He1pa]

Init ptr value when alloc

1. Does this PR affect any open issues?(Y/N) and add issue references (e.g. "fix #123", "re #123".):

• N
• Y fix failed in lib test chore: update kcl wasm lib#171

2. What is the scope of this PR (e.g. component or file name):

3. Provide a description of the PR(e.g. more details, effects, motivations or doc link):

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Other

4. Are there any breaking changes?(Y/N) and describe the breaking changes(e.g. more details, motivations or doc link):

• N
• Y

5. Are there test cases for these changes?(Y/N) select and add more details, references or doc links:

• Unit test
• Integration test
• Benchmark (add benchmark stats below)
• Manual test (add detailed scripts or steps below)
• Other

[coveralls]

Pull Request Test Coverage Report for Build 12349662488

Details

• 0 of 1 (0.0%) changed or added relevant line in 1 file are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.001%) to 70.678%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
kclvm/src/capi.rs	0	1	0.0%

Files with Coverage Reduction	New Missed Lines	%
kclvm/src/capi.rs	1	0.0%

Totals
Change from base Build 12349353137:	0.001%
Covered Lines:	52773
Relevant Lines:	74667

---

💛 - Coveralls

[zong-zhe]

LGTM