x86/mce/AMD: Add system physical address translation for AMD Fam17h

The Unified Memory Controllers (UMCs) on Fam17h log a normalized address
in their MCA_ADDR registers. We need to convert that normalized address
to a system physical address in order to support a few facilities:

1) To offline poisoned pages in DRAM proactively in the deferred error
   handler.

2) To print sysaddr and page info for DRAM ECC errors in EDAC.

[ Boris: fixes/cleanups ontop:

  * hi_addr_offset = 0 - no need for that branch. Stick it all under the
    HiAddrOffsetEn case. It confines hi_addr_offset's declaration too.

  * Move variables to the innermost scope they're used at so that we save
    on stack and not blow it up immediately on function entry.

  * Do not modify *sys_addr prematurely - we want to not exit early and
    have modified *sys_addr some, which callers get to see. We either
    convert to a sys_addr or we don't do anything. And we signal that with
    the retval of the function.

  * Rename label out -> out_err - because it is the error path.

  * No need to pr_err of the conversion failed case: imagine a
    sparsely-populated machine with UMCs which don't have DIMMs. Callers
    should look at the retval instead and issue a printk only when really
    necessary. No need for useless info in dmesg.

  * s/temp_reg/tmp/ and other variable names shortening => shorter code.

  * Use BIT() everywhere.

  * Make error messages more informative.

  *  Small build fix for the !CONFIG_X86_MCE_AMD case.

  * ... and more minor cleanups.
]

Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Aravind Gopalakrishnan <aravindksg.lkml@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20161122111133.mjzpvzhf7o7yl2oa@pd.tnic
[ Typo fixes. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>