Fix coverity issues on branch 8.4 #408

Job	Run time
check_update	2m 21s
address_ub_sanitizer	10m 58s
basic_clang	16s
basic_gcc	18s
buildtest	6m 49s
check-ansi	2m 9s
EC_POINTs_api_test	19m 17s
enable_non-default_options	18s
fips_and_ktls	16s
legacy	3m 31s
memory_sanitizer	22m 9s
minimal	2m 15s
no-deprecated	16s
no-legacy	19s
non-caching	4m 19s
no-shared (ubuntu-latest)	21s
ntls_memory_sanitizer	14m 33s
ntls_address_ub_sanitizer	9m 39s
no-shared (macos-latest)	2m 27s
phe_test	9s
symbol_prefix-test	1m 7s
threads_sanitizer	9s
external-test-pyca (1.51.0, 3.9)	1m 27s
ntls	9s
ntls-with-fips	26s
ntls-without-sm234	17s
out-of-source-and-install (ubuntu-latest)	17s
out-of-source-and-install (macos-latest)	3m 15s
zkp-build-test	16s
	1h 50m 3s

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