xfs: Add pquota fields where gquota is used.

Add project quota changes to all the places where group quota field
is used:
   * add separate project quota members into various structures
   * split project quota and group quotas so that instead of overriding
     the group quota members incore, the new project quota members are
     used instead
   * get rid of usage of the OQUOTA flag incore, in favor of separate
     group and project quota flags.
   * add a project dquot argument to various functions.

Not using the pquotino field from superblock yet.

Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com>
Reviewed-by: Ben Myers <bpm@sgi.com>
Signed-off-by: Ben Myers <bpm@sgi.com>

diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index 9112979..b55fd34 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -250,6 +250,7 @@
 	struct xfs_mount	*i_mount;	/* fs mount struct ptr */
 	struct xfs_dquot	*i_udquot;	/* user dquot */
 	struct xfs_dquot	*i_gdquot;	/* group dquot */
+	struct xfs_dquot	*i_pdquot;	/* project dquot */
 
 	/* Inode location stuff */
 	xfs_ino_t		i_ino;		/* inode number (agno/agino)*/