feat(esp_system): allow .bss to spill over into L2MEM above 0x4ff40000

This commit introduce SOC_MEM_NON_CONTIGUOUS_SRAM flag (that enebled for
esp32p4). If SOC_MEM_NON_CONTIGUOUS_SRAM is enabled:

- LDFLAGS+=--enable-non-contiguous-regions
- ldgen.py replaces "arrays[*]" from sections.ld.in with objects under
  SURROUND keyword. (e.g. from linker.lf: data -> dram0_data SURROUND(foo))
- "mapping[*]" - refers to all other data

If SOC_MEM_NON_CONTIGUOUS_SRAM, sections.ld.in file should contain at
least one block of code like this (otherwise it does not make sense):

  .dram0.bss (NOLOAD) :
  {
    arrays[dram0_bss]
    mapping[dram0_bss]
  } > sram_low

  .dram1.bss (NOLOAD) :
  {
    /* do not place here arrays[dram0_bss] because it may be splited
     * between segments */
    mapping[dram0_bss]
  } > sram_high

components/esp_bootloader_format/esp_bootloader_desc.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -10,7 +10,11 @@
 #include "sdkconfig.h"
 
 // Bootloader version info
-const __attribute__((weak)) __attribute__((section(".data_bootloader_desc"))) esp_bootloader_desc_t esp_bootloader_desc = {
+#if BOOTLOADER_BUILD
+__attribute__((section(".data_bootloader_desc")))
+#endif
+__attribute__((weak))
+const esp_bootloader_desc_t esp_bootloader_desc = {
     .magic_byte = ESP_BOOTLOADER_DESC_MAGIC_BYTE,
     .reserved = { 0 },
     .version = CONFIG_BOOTLOADER_PROJECT_VER,