optional partition layout for 2MB boards

useful for small -C3 boards with 2MB flash memory only. Based on suggestions  from https://github.com/Aircoookie/WLED/pull/2951 .

Needs `-D WLED_DISABLE_OTA` as OTA is not possible with 2MB.

RAM:   [==        ]  22.5% (used 73724 bytes from 327680 bytes)
Flash: [========= ]  94.9% (used 1492020 bytes from 1572864 bytes)

platformio.ini

@@ -1348,6 +1348,7 @@ extends = esp32_4MB_V4_S_base
 platform = espressif32@~5.2.0                  ;; alternative platform, might help in case you experience bootloops due to corrupted flash filesystem
 platform_packages =
 board = esp32-c3-devkitm-1
+;board_build.partitions = tools/WLED_ESP32_2MB_noOTA.csv ;; for boards with 2MB flash only (like some Ai-Thinker ESP32-C3-12F models)
 upload_speed = 256000 ;; 921600
 
 build_unflags = ${common.build_unflags}
@@ -1362,6 +1363,7 @@ build_flags = ${common.build_flags} ${esp32c3.build_flags}
   ${common_mm.build_flags_S} ${common_mm.build_flags_M}
   -Wno-misleading-indentation -Wno-format-truncation
   -D WLED_RELEASE_NAME=esp32c3dev_4MB_M
+  ; -D WLED_DISABLE_OTA          ;;  OTA is not possible for boards with 2MB flash only (like some Ai-Thinker ESP32-C3-12F models)
   ; -DARDUINO_USB_CDC_ON_BOOT=1  ;; enable CDC USB -> needed for debugging over serial USB
   -DARDUINO_USB_CDC_ON_BOOT=0    ;; disable CDC USB
   -D SERVERNAME='"WLED-C3"'

tools/WLED_ESP32_2MB_noOTA.csv

@@ -0,0 +1,5 @@
+# Name,   Type, SubType, Offset,  Size, Flags
+nvs,      data, nvs,     0x9000,    20K,
+otadata,  data, ota,     0xe000,    8K,
+app0,     app,  ota_0,   0x10000,   1536K,
+spiffs,   data, spiffs,  0x190000,  384K,