Decode properly flags of %ccr register on sparc64.

Decode properly flags of %ccr register on sparc64.

While at it, decode also properly one-bit flags for %fsr (accrued and
current exception flags were mixed up).

ChangeLog entry:
2017-03-21  Ivo Raisr  <ivo.raisr@oracle.com>

    	PR tdep/20928
    	* gdb/sparc-tdep.h (gdbarch_tdep) <sparc64_ccr_type>: New field.
    	* gdb/sparc64-tdep.c (sparc64_ccr_type): New function.
    	(sparc64_fsr_type): Fix %fsr decoding.

ChangeLog entry for testsuite:
2017-03-21  Ivo Raisr  <ivo.raisr@oracle.com>

    	PR tdep/20928
    	* gdb.arch/sparc64-regs.exp: New file.
    	* gdb.arch/sparc64-regs.S: Likewise.