Silence compiler warning

[hlinnaka]

I saw this compiler warning on my laptop:

pgxn/neon_walredo/walredoproc.c:178:10: warning: using the result of an assignment as a condition without parentheses [-Wparentheses]
        if (err = close_range_syscall(3, ~0U, 0)) {
            ~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pgxn/neon_walredo/walredoproc.c:178:10: note: place parentheses around the assignment to silence this warning
        if (err = close_range_syscall(3, ~0U, 0)) {
                ^
            (                                   )
pgxn/neon_walredo/walredoproc.c:178:10: note: use '==' to turn this assignment into an equality comparison
        if (err = close_range_syscall(3, ~0U, 0)) {
                ^
                ==
1 warning generated.

I'm not sure what compiler version or options cause that, but it's a good warning. Write the call a little differently, to avoid the warning and to make it a little more clear anyway. (The 'err' variable wasn't used for anything, so I'm surprised we were not seeing a compiler warning on the unused value, too.)

[github-actions[bot]]

2922 tests run: 2805 passed, 0 failed, 117 skipped (full report)

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Code coverage* (full report)

• functions: 32.5% (6875 of 21133 functions)
• lines: 50.1% (53648 of 106976 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
d3dc80ba303d573d9d44a7f3290f1b1b48b7e1a0 at 2024-06-25T11:55:59.759Z :recycle:}