cmake: fix pkgconfig and cmake interaction

Issue #454

CMakeLists.txt

@@ -228,18 +228,19 @@ list(APPEND CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
 if(PKG_CONFIG_FOUND)
     pkg_check_modules(ZLIB zlib)
     list(APPEND LXW_PRIVATE_INCLUDE_DIRS ${ZLIB_INCLUDE_DIRS})
-else(NOT ZLIB_FOUND)
+else()
     find_package(ZLIB "1.0" REQUIRED)
     list(APPEND LXW_PRIVATE_INCLUDE_DIRS ${ZLIB_INCLUDE_DIRS})
     message("zlib version: " ${ZLIB_VERSION})
 endif()
 
+
 # MINIZIP
 if(USE_SYSTEM_MINIZIP)
     if(PKG_CONFIG_FOUND)
         pkg_check_modules(MINIZIP minizip)
         list(APPEND LXW_PRIVATE_INCLUDE_DIRS ${MINIZIP_INCLUDE_DIRS}/..)
-    else(NOT MINIZIP_FOUND)
+    else()
         find_package(MINIZIP "1.0" REQUIRED)
         list(APPEND LXW_PRIVATE_INCLUDE_DIRS ${MINIZIP_INCLUDE_DIRS})
     endif()
@@ -288,7 +289,7 @@ if(USE_OPENSSL_MD5)
     if(PKG_CONFIG_FOUND)
         pkg_check_modules(LIBCRYPTO libcrypto)
         include_directories(${LIBCRYPTO_INCLUDE_DIRS})
-    else(NOT LIBCRYPTO_FOUND)
+    else()
         find_package(OpenSSL REQUIRED)
         include_directories(${OPENSSL_INCLUDE_DIR})
         message(STATUS "OpenSSL version: ${OPENSSL_VERSION}")
@@ -308,21 +309,24 @@ target_sources(${PROJECT_NAME}
     PRIVATE ${LXW_SOURCES}
     PUBLIC ${LXW_HEADERS}
 )
-if(ZLIB_LDFLAGS)
-    target_link_libraries(${PROJECT_NAME} LINK_PUBLIC ${ZLIB_LDFLAGS})
+if(ZLIB_LINK_LIBRARIES)
+    target_link_libraries(${PROJECT_NAME} LINK_PUBLIC ${ZLIB_LINK_LIBRARIES})
 else()
     target_link_libraries(${PROJECT_NAME} LINK_PUBLIC ${ZLIB_LIBRARIES})
 endif()
-if(MINIZIP_LDFLAGS)
-    target_link_libraries(${PROJECT_NAME} LINK_PUBLIC ${MINIZIP_LDFLAGS})
+
+if(MINIZIP_LINK_LIBRARIES)
+    target_link_libraries(${PROJECT_NAME} LINK_PUBLIC ${MINIZIP_LINK_LIBRARIES})
 else()
     target_link_libraries(${PROJECT_NAME} LINK_PUBLIC ${MINIZIP_LIBRARIES})
 endif()
-if(LIBCRYPTO_LDFLAGS)
-    target_link_libraries(${PROJECT_NAME} LINK_PUBLIC ${LIBCRYPTO_LDFLAGS})
+
+if(LIBCRYPTO_LINK_LIBRARIES)
+    target_link_libraries(${PROJECT_NAME} LINK_PUBLIC ${LIBCRYPTO_LINK_LIBRARIES})
 else()
     target_link_libraries(${PROJECT_NAME} LINK_PUBLIC ${LIB_CRYPTO} ${OPENSSL_CRYPTO_LIBRARY})
 endif()
+
 target_compile_definitions(${PROJECT_NAME} PRIVATE ${LXW_PRIVATE_COMPILE_DEFINITIONS})
 
 # /utf-8 needs VS2015 Update 2 or above.