compat: generic compat get/settimeofday

Nothing arch specific in get/settimeofday.  The details of the timeval
conversion varied a little from arch to arch, but all with the same
results.

Also add an extern declaration for sys_tz to linux/time.h because externs
in .c files are fowned upon.  I'll kill the externs in various other files
in a sparate patch.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net> [ sparc bits ]
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Grant Grundler <grundler@parisc-linux.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/mips/kernel/scall64-n32.S b/arch/mips/kernel/scall64-n32.S
index 324c549..e266b3a 100644
--- a/arch/mips/kernel/scall64-n32.S
+++ b/arch/mips/kernel/scall64-n32.S
@@ -214,7 +214,7 @@
 	PTR	sys_fchown
 	PTR	sys_lchown
 	PTR	sys_umask
-	PTR	sys32_gettimeofday
+	PTR	compat_sys_gettimeofday
 	PTR	compat_sys_getrlimit		/* 6095 */
 	PTR	compat_sys_getrusage
 	PTR	compat_sys_sysinfo
@@ -279,7 +279,7 @@
 	PTR	sys_chroot
 	PTR	sys_sync
 	PTR	sys_acct
-	PTR	sys32_settimeofday
+	PTR	compat_sys_settimeofday
 	PTR	compat_sys_mount		/* 6160 */
 	PTR	sys_umount
 	PTR	sys_swapon