esp32: IRAM_DATA_ATTR and IRAM_BSS_ATTR introduced

Using these attributes, .data and .bss can be placed in IRAM

Signed-off-by: Sachin Parekh <sachin.parekh@espressif.com>

components/esp32/ld/esp32_fragments.lf

@@ -40,6 +40,14 @@ entries:
 entries:
     .iram1+
 
+[sections:iram_data]
+entries:
+    .iram.data+
+
+[sections:iram_bss]
+entries:
+    .iram.bss+
+
 [sections:dram]
 entries:
     .dram1+
@@ -64,6 +72,8 @@ entries:
     bss -> dram0_bss
     common -> dram0_bss
     iram -> iram0_text
+    iram_data -> iram0_data
+    iram_bss -> iram0_bss
     dram -> dram0_data
     rtc_text -> rtc_text
     rtc_data -> rtc_data