[ESP32] Fix sntp initialization #928

Job	Run time
Build framework (macos-release-availability, -sdk macosx -configuration Release WARNING_CFLAGS=...	12m 2s
Build framework (ios-release, -sdk iphoneos -configuration Release WARNING_CFLAGS='${inherited} -...	9m 40s
Build framework (ios-debug, -sdk iphoneos -configuration Debug WARNING_CFLAGS='${inherited} -We...	6m 34s
Build framework (tvos-debug, -sdk appletvos -configuration Debug WARNING_CFLAGS='${inherited} -W...	9m 43s
Build framework (watchos-debug, -sdk watchos -configuration Debug WARNING_CFLAGS='${inherited}...	9m 10s
Build TV Casting Bridge example	9m 41s
Run framework tests (asan, -enableAddressSanitizer YES -enableUndefinedBehaviorSanitizer YES)	18m 9s
Run framework tests (asan-global-storage, -enableAddressSanitizer YES -enableUndefinedBehaviorSan...	18m 35s
Run framework tests (tsan, -enableThreadSanitizer YES)	19m 51s
	1h 53m 25s

Provide feedback