Bump SONAME to 2

libcriu.so used to have the SONAME

$ readelf -d lib/c/libcriu.so   | grep SONAME
 0x000000000000000e (SONAME)             Library soname: [libcriu.so.1]

The recent changes to libcriu (removed and added functions, changes from
`char *`-args to `const char *`) are breaking ABI and API. This requires
a new SONAME of 2. This patch changes the SONAME to 2:

$ readelf -d lib/c/libcriu.so   | grep SONAME
 0x000000000000000e (SONAME)             Library soname: [libcriu.so.2]
Signed-off-by: Adrian Reber <areber@redhat.com>

Makefile.versions

@@ -12,7 +12,7 @@ export CRIU_VERSION_EXTRA CRIU_VERSION_NAME CRIU_VERSION
 
 #
 # C library for CRIU.
-CRIU_SO_VERSION_MAJOR	:= 1
+CRIU_SO_VERSION_MAJOR	:= 2
 CRIU_SO_VERSION_MINOR	:= 0
 
 export CRIU_SO_VERSION_MAJOR CRIU_SO_VERSION_MINOR