Dwarf output for 6l.
Part 1, general scaffolding and pc/lc sections.

R=rsc, r, ken2
CC=golang-dev
https://golang.org/cl/1987042
diff --git a/src/cmd/6l/obj.c b/src/cmd/6l/obj.c
index 3b981a6..adcccb5 100644
--- a/src/cmd/6l/obj.c
+++ b/src/cmd/6l/obj.c
@@ -33,6 +33,7 @@
 #include	"../ld/lib.h"
 #include	"../ld/elf.h"
 #include	"../ld/macho.h"
+#include	"../ld/dwarf.h"
 #include	<ar.h>
 
 char	*noname		= "<none>";
@@ -575,6 +576,7 @@
 				histfrogp++;
 			} else
 				collapsefrog(s);
+                        dwarfaddfrag(s->value, s->name);
 		}
 		goto loop;
 	}
@@ -1058,4 +1060,3 @@
 		}
 	}
 }
-