x86: clean up mce= argument parsing slightly

Move the = into the __setup line.
Document the option in kernel-parameters.txt by adding a pointer
to the x86-64 specific documentation.

[ tglx: arch/x86 adaptation ]

Pointed out by Robert Day
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Documentation/kernel-parameters.txt

@@ -994,6 +994,8 @@ and is between 256 and 4096 characters. It is defined in the file
 
 	mce		[X86-32] Machine Check Exception
 
+	mce=option	[X86-64] See Documentation/x86_64/boot-options.txt
+
 	md=		[HW] RAID subsystems devices and level
 			See Documentation/md.txt.
 

arch/x86/kernel/mce_64.c

@@ -695,8 +695,6 @@ static int __init mcheck_disable(char *str)
    mce=nobootlog Don't log MCEs from before booting. */
 static int __init mcheck_enable(char *str)
 {
-	if (*str == '=')
-		str++;
 	if (!strcmp(str, "off"))
 		mce_dont_init = 1;
 	else if (!strcmp(str, "bootlog") || !strcmp(str,"nobootlog"))
@@ -709,7 +707,7 @@ static int __init mcheck_enable(char *str)
 }
 
 __setup("nomce", mcheck_disable);
-__setup("mce", mcheck_enable);
+__setup("mce=", mcheck_enable);
 
 /* 
  * Sysfs support