btrfs-progs: merge qgroup.c into cmds/qgroup.c

The contents of top level qgroups.c is only for command line output and
filtering, we already have cmds/qgroup.c for that so merge the files.

Signed-off-by: David Sterba <dsterba@suse.com>

Makefile

@@ -144,7 +144,7 @@ CHECKER_FLAGS := -include $(check_defs) -D__CHECKER__ \
 	-U_FORTIFY_SOURCE -Wdeclaration-after-statement -Wdefault-bitfield-sign
 
 objects = kernel-shared/dir-item.o \
-	  qgroup.o kernel-lib/list_sort.o props.o \
+	  kernel-lib/list_sort.o props.o \
 	  kernel-shared/ulist.o check/qgroup-verify.o kernel-shared/backref.o \
 	  common/string-table.o common/task-utils.o \
 	  kernel-shared/inode.o kernel-shared/file.o common/help.o cmds/receive-dump.o \