fix omission of microblaze user.h definitions

arch/microblaze/bits/user.h

-/* FIXME: missing in kernel? */
+struct user_fpregs_struct {
+	long cwd, swd, twd, fip, fcs, foo, fos, st_space[20];
+};
+
+struct user_regs_struct {
+	unsigned grp[32], pc, msr, ear, esr, fsr, btr, pvr[12];
+};
+
+struct user {
+	struct user_regs_struct regs;
+	int u_fpvalid;
+	struct user_fpregs_struct elf_fpregset_t;
+	unsigned long u_tsize, u_dsize, u_ssize, start_code, start_stack;
+	long signal;
+	int reserved;
+	struct user_regs_struct *u_ar0;
+	struct user_fpregs_struct *u_fpstate;
+	unsigned long magic;
+	char u_comm[32];
+	int u_debugreg[8];
+};
+
+#define ELF_NGREG 50
+typedef unsigned long elf_greg_t, elf_gregset_t[ELF_NGREG];
+typedef struct user_fpregs_struct elf_fpregset_t;