libsrslte_rf: add library version

This patch adds version string to the 'libsrslte_rf' library.
This results in the library being built as
    libsrslte_rf.so.20.04.2
with the following symbolic links
    libsrslte_rf.so.0 -> libsrslte_rf.so.20.04.2
    libsrslte_rf.so -> libsrslte_rf.so.0

The SRSLTE_SOVERSION variable should be increased with each backwards
incompatible change of the library.

Signed-off-by: Jan Remes <jan.remes@invasys.com>

cmake/modules/SRSLTEVersion.cmake

@@ -22,3 +22,4 @@ SET(SRSLTE_VERSION_MAJOR 20)
 SET(SRSLTE_VERSION_MINOR 10)
 SET(SRSLTE_VERSION_PATCH 0)
 SET(SRSLTE_VERSION_STRING "${SRSLTE_VERSION_MAJOR}.${SRSLTE_VERSION_MINOR}.${SRSLTE_VERSION_PATCH}")
+SET(SRSLTE_SOVERSION 0)

lib/src/phy/rf/CMakeLists.txt

@@ -66,6 +66,7 @@ if(RF_FOUND)
 
   add_library(srslte_rf SHARED ${SOURCES_RF})
   target_link_libraries(srslte_rf srslte_rf_utils srslte_phy)
+  set_target_properties(srslte_rf PROPERTIES VERSION ${SRSLTE_VERSION_STRING} SOVERSION ${SRSLTE_SOVERSION})
   
   if (UHD_FOUND)
     target_link_libraries(srslte_rf ${UHD_LIBRARIES})