depends: Rename cmake_system -> cmake_system_name

depends/funcs.mk

@@ -191,7 +191,7 @@ ifeq ($($(1)_type),build)
 $(1)_cmake += -DCMAKE_INSTALL_RPATH:PATH="$$($($(1)_type)_prefix)/lib"
 else
 ifneq ($(host),$(build))
-$(1)_cmake += -DCMAKE_SYSTEM_NAME=$($(host_os)_cmake_system)
+$(1)_cmake += -DCMAKE_SYSTEM_NAME=$($(host_os)_cmake_system_name)
 $(1)_cmake += -DCMAKE_C_COMPILER_TARGET=$(host)
 $(1)_cmake += -DCMAKE_CXX_COMPILER_TARGET=$(host)
 endif