Attribute Macro esp32_hal_proc_macros::ram

#[ram]

This attribute allows placing statics, constants and functions into ram.

Options that can be specified are rtc_slow, rtc_fast or external to use the RTC slow, RTC fast ram or external SPI RAM instead of the normal SRAM.

The uninitialized option will skip initialization of the memory (e.g. to persist it across resets or deep sleep mode for the RTC RAM)