linker: warn about orphan sections

(Previous patch set was reverted due to issue with priv_stack.
 Resubmitting after fixing the faults caused by priv_stack.noinit
 not at the end of RAM.)

This adds a linker flag and necessary changes to linker scripts
so that linker will warn about orphan sections.

Relates to #5534.

Fixes #10473, #10474, #10515.

Signed-off-by: Daniel Leung <daniel.leung@intel.com>

soc/xtensa/esp32/linker.ld

@@ -64,6 +64,9 @@ PROVIDE(_memmap_reset_vector = 0x40000400);
 
 SECTIONS
 {
+
+#include <linker/rel-sections.ld>
+
   /* RTC fast memory holds RTC wake stub code,
      including from any source file named rtc_wake_stub*.c
   */
@@ -252,4 +255,12 @@ SECTIONS
 #ifdef CONFIG_GEN_ISR_TABLES
 #include <linker/intlist.ld>
 #endif
+
+#include <linker/debug-sections.ld>
+
+  SECTION_PROLOGUE(.xtensa.info, 0,)
+  {
+    *(.xtensa.info)
+  }
+
 }