Add overloads to support __FlashStringHelper like ESP8266 has them.

[dok-net]

Fixes #8108

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[github-actions]

External libraries build test

Library	ESP32	ESP32C3	ESP32S2	ESP32S3
Adafruit NeoPixel	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
ArduinoBLE	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	N/A	1 ✅ -> 1 ✅
ESP32Servo	4 ✅ -> 4 ✅	4 ✅ -> 4 ✅	4 ✅ -> 4 ✅	4 ✅ -> 4 ✅
ESPAsyncWebServer	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️	4 ❌ -> 4 ❌	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️
FastLED	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
IRremote	1 ⚠️ -> 1 ⚠️	1 ❌ -> 1 ❌	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅

[github-actions]

External libraries build test

Library	ESP32	ESP32C3	ESP32S2	ESP32S3
Adafruit NeoPixel	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
ArduinoBLE	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	N/A	1 ✅ -> 1 ✅
ESP32Servo	4 ✅ -> 4 ✅	4 ✅ -> 4 ✅	4 ✅ -> 4 ✅	4 ✅ -> 4 ✅
ESPAsyncWebServer	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️	4 ❌ -> 4 ❌	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️
FastLED	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
IRremote	1 ⚠️ -> 1 ⚠️	1 ❌ -> 1 ❌	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅

[mrengineer7777]

Restores previous definitions for F and FPSTR in Wstring.h. This should fix breaking changes in other libraries. I'm not sure about the other changes introduced by this PR.

[me-no-dev]

Can you pease split the changes into separate PRs. There seem to be three unrelated changes.
F() used to be #define F(string_literal) (FPSTR(PSTR(string_literal)))

[dok-net]

Can you pease split the changes into separate PRs.

Oh dear, I partly understand where this request is coming from, but honestly, I don't have time on my hands to do this RIGHT until 2 weekends away from now. And I don't know how much better it will be in two or three steps. Seeing the first attempt, just reverting the macros breaks something else. I honestly have to ask you to review this as is, because the dependencies are just there. Of course it could be attempted to find out which of the changes, macros, libs, could perhaps stand without the other, probably the libs because they ADD wrappers now, but for that exact same reason, why not review this PR as it stands, pleeeeze?

I'm sorry the first PR didn't work for some 3rd party libs.

[dok-net]

F() used to be #define F(string_literal) (FPSTR(PSTR(string_literal)))

The reverted macros now just drop the PSTR, becauses it's a dummy on ESP32, and will always be (?):
cores/esp32/pgmspace.h:#define PSTR(s) (s)

[tueddy]

Please add this to 2.0.9, it's a high visible show stopper

[github-actions]

External libraries build test

Library	ESP32	ESP32C3	ESP32S2	ESP32S3
Adafruit NeoPixel	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
ArduinoBLE	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	N/A	1 ✅ -> 1 ✅
ESP32Servo	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
ESPAsyncWebServer	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️	4 ❌ -> 4 ❌	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️
FastLED	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
IRremote	1 ⚠️ -> 1 ⚠️	1 ❌ -> 1 ❌	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
MFRC522	1 ❌ -> 1 ✅	1 ❌ -> 1 ✅	1 ❌ -> 1 ✅	1 ❌ -> 1 ✅
WS2812FX	1 ❌ -> 1 ❌	1 ❌ -> 1 ❌	1 ❌ -> 1 ❌	1 ❌ -> 1 ❌

[github-actions]

External libraries build test

Library	ESP32	ESP32C3	ESP32S2	ESP32S3
Adafruit NeoPixel	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
ArduinoBLE	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	N/A	1 ✅ -> 1 ✅
ESP32Servo	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
ESPAsyncWebServer	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️	4 ❌ -> 4 ❌	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️	3 ✅ 1 ⚠️ -> 3 ✅ 1 ⚠️
FastLED	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
IRremote	1 ⚠️ -> 1 ⚠️	1 ❌ -> 1 ❌	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
MFRC522	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅
WS2812FX	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅	1 ✅ -> 1 ✅