Minidumper: Get the nexe's build ID from PT_NOTE when available

src/include/elf32.h

Index: src/include/elf32.h
diff --git a/src/include/elf32.h b/src/include/elf32.h
index 52163b062c7cc7177a7b8a318dc314a6b959f671..b12abfab647b1f617ee162246bb58cef8b442e62 100644
--- a/src/include/elf32.h
+++ b/src/include/elf32.h
@@ -84,6 +84,12 @@ typedef struct {
   Elf32_Word  sh_entsize;
 } Elf32_Shdr;
 
+typedef struct {
+  Elf32_Word n_namesz;
+  Elf32_Word n_descsz;
+  Elf32_Word n_type;
+} Elf32_Nhdr;
+
 /*
  * The auxiliary vector is passed on the stack between ELF loaders,
  * dynamic linkers, and program startup code.  The gratuitous union