build: Rename PACKAGE_* variables to CLIENT_*

The use of `PACKAGE_NAME` for the project's variable name is
problematic, as this name is commonly used in CMake's interface
variables. If third-party CMake code handles with scopes improperly,
our `PACKAGE_NAME` variable could end up with an unexpected value.

This change avoids such conflicts by renaming all `PACKAGE_*` variables
to `CLIENT_*`.

cmake/module/GenerateSetupNsi.cmake

@@ -5,8 +5,8 @@
 function(generate_setup_nsi)
   set(abs_top_srcdir ${PROJECT_SOURCE_DIR})
   set(abs_top_builddir ${PROJECT_BINARY_DIR})
-  set(PACKAGE_URL ${PROJECT_HOMEPAGE_URL})
-  set(PACKAGE_TARNAME "bitcoin")
+  set(CLIENT_URL ${PROJECT_HOMEPAGE_URL})
+  set(CLIENT_TARNAME "bitcoin")
   set(BITCOIN_GUI_NAME "bitcoin-qt")
   set(BITCOIN_DAEMON_NAME "bitcoind")
   set(BITCOIN_CLI_NAME "bitcoin-cli")

cmake/module/Maintenance.cmake

@@ -98,7 +98,7 @@ function(add_macos_deploy_target)
     file(CONFIGURE OUTPUT ${macos_app}/Contents/Resources/empty.lproj CONTENT "")
     configure_file(${PROJECT_SOURCE_DIR}/src/qt/res/icons/bitcoin.icns ${macos_app}/Contents/Resources/bitcoin.icns NO_SOURCE_PERMISSIONS COPYONLY)
     file(CONFIGURE OUTPUT ${macos_app}/Contents/Resources/Base.lproj/InfoPlist.strings
-      CONTENT "{ CFBundleDisplayName = \"@PACKAGE_NAME@\"; CFBundleName = \"@PACKAGE_NAME@\"; }"
+      CONTENT "{ CFBundleDisplayName = \"@CLIENT_NAME@\"; CFBundleName = \"@CLIENT_NAME@\"; }"
     )
 
     add_custom_command(
@@ -109,7 +109,7 @@ function(add_macos_deploy_target)
       VERBATIM
     )
 
-    string(REPLACE " " "-" osx_volname ${PACKAGE_NAME})
+    string(REPLACE " " "-" osx_volname ${CLIENT_NAME})
     if(CMAKE_HOST_APPLE)
       add_custom_command(
         OUTPUT ${PROJECT_BINARY_DIR}/${osx_volname}.zip