esp32/boards: Increase 512 bytes limit on ULP programs to 2040.

Allow esp32.ULP.load_binary() to use the maximum amount of memory available
again, which is 2040 bytes unless MICROPY_HW_RTC_USER_MEM_MAX is
customized.

This value regressed in 3d49b157b8

ports/esp32/boards/sdkconfig.base

@@ -49,6 +49,7 @@ CONFIG_MBEDTLS_ASYMMETRIC_CONTENT_LEN=y
 
 # ULP coprocessor support
 CONFIG_ESP32_ULP_COPROC_ENABLED=y
+CONFIG_ESP32_ULP_COPROC_RESERVE_MEM=2040
 
 # For cmake build
 CONFIG_ESPTOOLPY_FLASHSIZE_4MB=y