x86: only call early_init_amd one time

Andi's patch
"
    x86: move X86_FEATURE_CONSTANT_TSC into early cpu feature detection

    Need this in the next patch in time_init and that happens early.

    This includes a minor fix on i386 where early_intel_workarounds()
    [which is now called early_init_intel] really executes early as
    the comments say.
"
calling early_init_amd in early_identify_cpu and identify_cpu two times.

this patch remove the one in identify_cpu

Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>