Fix more testcases with standard_output_file.

Since
	commit 2151ccc56c
	Author: Simon Marchi <simon.marchi@ericsson.com>
	Date:   Mon Feb 8 14:02:36 2016 -0500
	    Always organize test artifacts in a directory hierarchy
these testfiles could not build.

gdb/testsuite/ChangeLog
2016-02-15  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.arch/i386-gnu-cfi.exp: Use standard_output_file.
	* gdb.arch/i386-prologue.exp: Likewise.
	* gdb.arch/i386-size.exp: Likewise.

gdb/testsuite/ChangeLog

@@ -1,3 +1,9 @@
+2016-02-15  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	* gdb.arch/i386-gnu-cfi.exp: Use standard_output_file.
+	* gdb.arch/i386-prologue.exp: Likewise.
+	* gdb.arch/i386-size.exp: Likewise.
+
 2016-02-15  Simon Marchi  <simon.marchi@ericsson.com>
 
 	* gdb.base/wrong_frame_bt_full.exp: Use standard_output_file to

gdb/testsuite/gdb.arch/i386-gnu-cfi.exp

@@ -31,7 +31,7 @@ if { ![is_x86_like_target] } then {
 set testfile "i386-gnu-cfi"
 set srcfilec ${testfile}.c
 set srcfileasm ${testfile}-asm.S
-set binfile ${objdir}/${subdir}/${testfile}
+set binfile [standard_output_file ${testfile}]
 
 # some targets have leading underscores on assembly symbols.
 set additional_flags [gdb_target_symbol_prefix_flags]

gdb/testsuite/gdb.arch/i386-prologue.exp

@@ -28,7 +28,7 @@ if { ![is_x86_like_target] } then {
 
 set testfile "i386-prologue"
 set srcfile ${testfile}.c
-set binfile ${objdir}/${subdir}/${testfile}
+set binfile [standard_output_file ${testfile}]
 
 # some targets have leading underscores on assembly symbols.
 set additional_flags [gdb_target_symbol_prefix_flags]

gdb/testsuite/gdb.arch/i386-size.exp

@@ -27,7 +27,7 @@ if { ![is_x86_like_target] } then {
 
 set testfile "i386-size"
 set srcfile ${testfile}.c
-set binfile ${objdir}/${subdir}/${testfile}
+set binfile [standard_output_file ${testfile}]
 
 # some targets have leading underscores on assembly symbols.
 set additional_flags [gdb_target_symbol_prefix_flags]