Add some functions to PCF8523 (Alarm)

[aurelihein]

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• Describe the scope of your change--i.e. what the change does and what parts
  of the code were modified. This will help us understand any risks of integrating
  the code.
  This PR just add few functions to PCF8523, and add Alarm function

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  doesn't apply to a supported platform of the library please mention it.
  It should work straight everywhere

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It is straight forward

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After reviewing the guidelines above you can delete this text from the pull request.

Let me know if you need any modification
Best regards,
Aurelien BOUIN

[edgar-bonet]

I have a few suggestions that could help make this pull request better. Note, though, that this is just my opinion: I am only a contributor here, not a maintainer.

• Name the new methods using camelCase rather than snake_case, as this is the style used in the current code.
• Make sure your code does not introduce new warnings, even when the IDE is configured to show “All” warnings. Specifically, you should have seen a couple of warning: '<<' in boolean context that reveal actual coding errors.
• Test the code, even if it is straight forward.
• Write a more descriptive commit message.
• When writing the pull request cover letter, remove the default text with the guidelines.
• If the CI reports a failure, check what is wrong and fix it.

[edgar-bonet]

Suggested change

	return (read_register(PCF8523_CONTROL_2) && (1 << 3));//Check AF
	return (read_register(PCF8523_CONTROL_2) & (1 << 3));//Check AF

[edgar-bonet]

Suggested change

	if(read_register(PCF8523_CONTROL_1) && (1<<1)){
	if(read_register(PCF8523_CONTROL_1) & (1<<1)){

[edgar-bonet]

Debug statements probably do not belong to this pull request.

[edgar-bonet]

Suggested change

	#ifdef DEBUG_RTCLIB
	Serial.printf("I2C_W(0x%02X,0x%02X)\n",reg,val);
	#endif /* DEBUG_RTCLIB */

[edgar-bonet]

Suggested change

	#ifdef DEBUG_RTCLIB
	DEBUG_RTCLIB.printf("I2C_R(0x%02X)=0x%02X\n",reg,buffer[0]);
	#endif /* DEBUG_RTCLIB */

[aurelihein]

Thank you @edgar-bonet for your time
I have updated the PR following your advice

[edgar-bonet]

Great!

LGTM, but note that clang-format is being picky about your formatting, hence the CI failure. You may want to

clang-format -i src/*

or, alternatively, patch the output of the clang-format test failure to git apply.

[aurelihein]

Thanks again @edgar-bonet
clang-format applied