Suggest both options to build Flang-RT

Author: Meinersbur

flang/CMakeLists.txt

@@ -247,13 +247,13 @@ if (FLANG_INCLUDE_RUNTIME)
     message(WARNING "Building Flang-RT using LLVM_ENABLE_RUNTIMES. FLANG_INCLUDE_RUNTIME=${FLANG_INCLUDE_RUNTIME} ignored.")
     set(FLANG_INCLUDE_RUNTIME OFF)
   else ()
-     message(STATUS "Building flang_rt in-tree")
+     message(STATUS "Building Flang-RT in-tree")
   endif ()
 else ()
   if ("flang-rt" IN_LIST LLVM_ENABLE_RUNTIMES)
-    message(STATUS "Building Flang-RT using LLVM_ENABLE_RUNTIMES.")
+    message(STATUS "Building Flang-RT using LLVM_ENABLE_RUNTIMES")
   else ()
-    message(STATUS "Not building Flang-RT. For a usable Fortran toolchain, compile a standalone Flang-RT")
+    message(STATUS "Not building Flang-RT. For a usable Fortran toolchain, either add LLVM_ENABLE_RUNTIMES=flang-rt, or compile a standalone Flang-RT.")
   endif ()
 endif ()