Add RMII Ethernet support for ESP32-P4

[me-no-dev]

Also adds default config to the P4 pins_arduino.h

[github-actions[bot]]

	Warnings
:warning:	The Pull Request description looks very brief, please check if more details can be added.
:warning:	The **target branch** for this Pull Request **must be the default branch** of the project (`master`). If you would like to add this feature to a different branch, please state this in the PR description and we will consider it.

	Messages
:book:	You might consider squashing your 4 commits (simplifying branch history).

👋 Hello me-no-dev, we appreciate your contribution to this project!

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Generated by :no_entry_sign: dangerJS against 9363ce883888ade63044dc55323bfe139c4dc9f1

[github-actions[bot]]

Memory usage test (comparing PR against master branch)

The table below shows the summary of memory usage change (decrease - increase) in bytes and percentage for each target.

Memory	FLASH [bytes]		FLASH [%]		RAM [bytes]		RAM [%]
Target	DEC	INC	DEC	INC	DEC	INC	DEC	INC
ESP32P4	0	0	0.00	0.00	0	0	0.00	0.00
ESP32S3	0	:bangbang: +17K	0.00	:bangbang: +2.74	0	:bangbang: +2K	0.00	:bangbang: +8.27
ESP32S2	0	:bangbang: +14K	0.00	:bangbang: +2.34	0	:bangbang: +2K	0.00	:bangbang: +8.80
ESP32C3	0	:bangbang: +20K	0.00	:bangbang: +3.33	0	:bangbang: +2K	0.00	:bangbang: +10.32
ESP32C6	0	:bangbang: +35K	0.00	:bangbang: +3.95	0	:bangbang: +22K	0.00	:bangbang: +127.95
ESP32H2	0	:bangbang: +11K	0.00	:bangbang: +2.12	0	:bangbang: +22K	0.00	:bangbang: +126.07
ESP32	0	:bangbang: +14K	0.00	:bangbang: +2.16	0	:warning: +1352	0.00	:bangbang: +3.19

Click to expand the detailed deltas report [usage change in BYTES]

Target	ESP32P4		ESP32S3		ESP32S2		ESP32C3		ESP32C6		ESP32H2		ESP32
Example	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM	FLASH	RAM
Ethernet/examples/ETH_TLK110	-	-	-	-	-	-	-	-	-	-	-	-	:bangbang: +11K	:warning: +800
Ethernet/examples/ETH_W5500_Arduino_SPI	-	-	:bangbang: +15K	:warning: +1940	:bangbang: +12K	:warning: +1668	:bangbang: +17K	:warning: +1744	:bangbang: +19K	:bangbang: +22K	:bangbang: +11K	:bangbang: +22K	:bangbang: +8K	:warning: +736
Ethernet/examples/ETH_W5500_IDF_SPI	-	-	:bangbang: +14K	:warning: +1908	:bangbang: +11K	:warning: +1620	:bangbang: +17K	:warning: +1744	:bangbang: +19K	:bangbang: +22K	:bangbang: +11K	:bangbang: +22K	:bangbang: +7K	:warning: +672
Ethernet/examples/ETH_WIFI_BRIDGE	-	-	:bangbang: +17K	:bangbang: +2K	:bangbang: +14K	:bangbang: +2K	:bangbang: +20K	:bangbang: +2K	:bangbang: +35K	:bangbang: +4K	-	-	:bangbang: +14K	:warning: +1352
Ethernet/examples/ETH_LAN8720	-	-	-	-	-	-	-	-	-	-	-	-	:bangbang: +11K	:warning: +800

[github-actions[bot]]

Test Results

 56 files  ±0   56 suites  ±0   4m 17s :stopwatch: -1s  21 tests ±0   21 :white_check_mark: ±0  0 :zzz: ±0  0 :x: ±0  135 runs  ±0  135 :white_check_mark: ±0  0 :zzz: ±0  0 :x: ±0 

Results for commit 9363ce88. ± Comparison against base commit 612fc4c4.

:recycle: This comment has been updated with latest results.