SPARC should be recognized as a 64-bit CPU.  Nothing seems to break with or
without this patch, but a few dictionary sizes are bigger with it, and the
banner changes to indicate the 64-bitness.

This is suitable for passing upstream.

--- p7zip_15.14.1/C/CpuArch.h	2016-02-16 22:27:16.000000000 -0800
+++ p7zip_15.14.1/C/CpuArch.h	2016-04-22 17:34:27.655604054 -0700
@@ -27,7 +27,8 @@
 #if defined(MY_CPU_AMD64) \
     || defined(_M_IA64) \
     || defined(__AARCH64EL__) \
-    || defined(__AARCH64EB__)
+    || defined(__AARCH64EB__) \
+    || defined(__sparcv9)
   #define MY_CPU_64BIT
 #endif