[cmake] fix typo in fitsio

Author: ferdymercury

cmake/modules/SearchInstalledSoftware.cmake

@@ -956,8 +956,8 @@ if(fitsio OR builtin_cfitsio)
     ROOT_CHECK_CONNECTION_AND_DISABLE_OPTION("builtin_cfitsio")
   endif()
   if(builtin_cfitsio)
-    if(NOT cfitsio)
-       message(WARNING "cfitsio is OFF, hence ignoring the activated setting 'builtin_cfitsio'")
+    if(NOT fitsio)
+       message(WARNING "fitsio is OFF, hence ignoring the activated setting 'builtin_cfitsio'")
     else()
       add_library(CFITSIO::CFITSIO STATIC IMPORTED GLOBAL)
       add_subdirectory(builtins/cfitsio)