ESP32-S2: Fix creation of .rwdata_dummy section

[bjoernQ]

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Submission Checklist 📝

• I have updated existing examples or added new ones (if applicable).
• I have used cargo xtask fmt-packages command to ensure that all changed code is formatted correctly.
• My changes were added to the CHANGELOG.md in the proper section.
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Pull Request Details 📖

Description

Previously the .rwdata_dummy section was setting the location counter based on ORIGIN(RWDATA) which is defined as dram_seg ( RW ) : ORIGIN = 0x3FFB0000 + RESERVE_CACHES + VECTORS_SIZE, len = 188k - RESERVE_CACHES - VECTORS_SIZE

Instead of using origin we can use the current location counter and add SIZEOF(.rwtext) + SIZEOF(.rwtext.wifi) to fix it

Testing

CI and running e.g. wifi_embassy_dhcp or psram examples

[jessebraham]

Thanks!