Don't forward-declare struct objfile in dwarf2/frame.h

dwarf2/frame.h forward-declares struct objfile, but there's no need
for this.

gdb/ChangeLog
2020-02-11  Tom Tromey  <tom@tromey.com>

	* dwarf2/frame.h (struct objfile): Don't forward declare.

Change-Id: I4d54d46ac9422eeb64dc5f0b934792e77a875aa5

gdb/ChangeLog

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 91d7cec..72a6292 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2020-02-11  Tom Tromey  <tom@tromey.com>
+
+	* dwarf2/frame.h (struct objfile): Don't forward declare.
+
 2020-02-11  Christian Biesinger  <cbiesinger@google.com>
 
 	* cris-tdep.c (cris_supply_gregset): Change signature to match

gdb/dwarf2/frame.h

diff --git a/gdb/dwarf2/frame.h b/gdb/dwarf2/frame.h
index a0ec361..dd7315c 100644
--- a/gdb/dwarf2/frame.h
+++ b/gdb/dwarf2/frame.h
@@ -23,7 +23,6 @@
 #define DWARF2_FRAME_H 1
 
 struct gdbarch;
-struct objfile;
 struct frame_info;
 struct dwarf2_per_cu_data;
 struct agent_expr;