cmake - fix SOVERSION property used for libcapstone.so (#914)

It was set as a global property before, but cmake appears to ignore that,
even after the following fix:
-set_property(GLOBAL PROPERTY SOVERSION SOVERSION ${VERSION_MAJOR})
+set_property(GLOBAL PROPERTY SOVERSION ${VERSION_MAJOR})

So this patch removes the global property, and SOVERSION is now specified as
a target specific property. The result of the cmake install target seems better:

Before:

$ ls -la lib
4375834 May  1 16:05 libcapstone.a
3510040 May  1 16:05 libcapstone.so

After:

$ ls -la lib
4375834 May  1 16:05 libcapstone.a
     16 May  1 16:08 libcapstone.so -> libcapstone.so.4
     20 May  1 16:08 libcapstone.so.4 -> libcapstone.so.4.0.0
3510040 May  1 16:08 libcapstone.so.4.0.0

The SOVERSION property triggers symlink creation in cmake, see:
https://cmake.org/cmake/help/v3.0/prop_tgt/SOVERSION.html
1 file changed