Remove extra output directory level for Ada tests

The output of Ada tests create a layout where the test name
("formatted_ref" in this example) appears twice:

outputs
└── gdb.ada
    └── formatted_ref
        └── formatted_ref
            ├── b~formatted_ref.adb
            ├── b~formatted_ref.ads
            ├── b~formatted_ref.ali
            ├── b~formatted_ref.o
            ├── defs.ali
            ├── defs.o
            ├── formatted_ref
            ├── formatted_ref.ali
            └── formatted_ref.o

This causes a problem when testing with the native-gdbserver board, when
the binary has the same name as the test.  When gdb_remote_download is
called to upload the compiled binary, the implementation for
native-gdbserver copies it in the standard output directory (in
outputs/gdb.ada/formatted_ref).  However, there is already a directory
named formatted_ref in there, so the copy fails and gdbserver isn't able
to load the binary.

This patch bypasses the problem by removing the extra directory level.
The compiled binary will already be in its final location in the
standard output directory, so the copy will effectively be a no-op.

gdb/testsuite/ChangeLog:

	* lib/ada.exp: Remove extra directory level in build directory.
	* gdb.ada/cond_lang.exp: Likewise.
	* gdb.ada/exec_changed.exp: Likewise.
	* gdb.ada/lang_switch.exp: Likewise.

gdb/testsuite/ChangeLog

@@ -1,3 +1,10 @@
+2016-07-06  Simon Marchi  <simon.marchi@ericsson.com>
+
+	* lib/ada.exp: Remove extra directory level in build directory.
+	* gdb.ada/cond_lang.exp: Likewise.
+	* gdb.ada/exec_changed.exp: Likewise.
+	* gdb.ada/lang_switch.exp: Likewise.
+
 2016-07-06  Manish Goregaokar  <manish@mozilla.com>
 
 	* simple.rs: Add test for raw pointer subscripting

gdb/testsuite/gdb.ada/cond_lang.exp

@@ -17,8 +17,8 @@ load_lib "ada.exp"
 
 standard_ada_testfile a
 
-set cfile "${testdir}/foo"
+set cfile "foo"
-set csrcfile ${srcdir}/${subdir}/${cfile}.c
+set csrcfile ${srcdir}/${subdir}/${testdir}/${cfile}.c
 set cobject [standard_output_file ${cfile}.o]
 
 gdb_compile "${csrcfile}" "${cobject}" object [list debug]

gdb/testsuite/gdb.ada/exec_changed.exp

@@ -32,9 +32,8 @@ if {[gdb_compile_ada "${srcfile}" "${binfile}$EXEEXT" executable {debug}] != ""}
 }
 
 # Build the second test program
-set testfile2 "${testdir}/second"
+set srcfile2 ${srcdir}/${subdir}/${testdir}/second.adb
-set srcfile2 ${srcdir}/${subdir}/${testfile2}.adb
+set binfile2 [standard_output_file second$EXEEXT]
-set binfile2 [standard_output_file ${testfile2}$EXEEXT]
 
 if {[gdb_compile_ada "${srcfile2}" "${binfile2}" executable {debug}] != ""} {
     return -1
@@ -42,7 +41,7 @@ if {[gdb_compile_ada "${srcfile2}" "${binfile2}" executable {debug}] != ""} {
 
 # Start with a fresh gdb.
 
-set common_binfile [standard_output_file ${testdir}/common$EXEEXT]
+set common_binfile [standard_output_file common$EXEEXT]
 
 gdb_start
 gdb_reinitialize_dir $srcdir/$subdir

gdb/testsuite/gdb.ada/lang_switch.exp

@@ -16,8 +16,8 @@
 load_lib "ada.exp"
 
 standard_ada_testfile lang_switch
-set cfile "${testdir}/foo"
+set cfile "foo"
-set csrcfile ${srcdir}/${subdir}/${cfile}.c
+set csrcfile ${srcdir}/${subdir}/${testdir}/${cfile}.c
 set cobject [standard_output_file ${cfile}.o]
 
 gdb_compile "${csrcfile}" "${cobject}" object [list debug]

gdb/testsuite/lib/ada.exp

@@ -73,9 +73,8 @@ proc standard_ada_testfile {base_file {dir ""}} {
     } else {
 	set testdir $dir
     }
-    set testfile $testdir/$base_file
-    set srcfile $srcdir/$subdir/$testfile.adb
-    set binfile [standard_output_file $testfile]
 
-    file mkdir [standard_output_file $testdir]
+    set testfile $base_file
+    set srcfile $srcdir/$subdir/$testdir/$testfile.adb
+    set binfile [standard_output_file $testfile]
 }