Find{BLAS,LAPACK}: Simplify check_function_exists state maintenance

Now that `CHECK_{BLAS,LAPACK}_LIBRARIES` are functions, we can set
`CMAKE_REQUIRED_QUIET` locally without affecting the global state.

Modules/FindBLAS.cmake

@@ -176,10 +176,7 @@ if(CMAKE_Fortran_COMPILER_LOADED)
 else()
   include(${CMAKE_CURRENT_LIST_DIR}/CheckFunctionExists.cmake)
 endif()
-include(${CMAKE_CURRENT_LIST_DIR}/CMakePushCheckState.cmake)
 include(${CMAKE_CURRENT_LIST_DIR}/FindPackageHandleStandardArgs.cmake)
-cmake_push_check_state()
-set(CMAKE_REQUIRED_QUIET ${BLAS_FIND_QUIETLY})
 
 if(BLA_PREFER_PKGCONFIG)
   find_package(PkgConfig)
@@ -261,6 +258,7 @@ function(CHECK_BLAS_LIBRARIES LIBRARIES _prefix _name _flags _list _deps _addlib
   if(_libraries_work)
     # Test this combination of libraries.
     set(CMAKE_REQUIRED_LIBRARIES ${_flags} ${_libraries} ${_deps})
+    set(CMAKE_REQUIRED_QUIET ${BLAS_FIND_QUIETLY})
     if(CMAKE_Fortran_COMPILER_LOADED)
       check_fortran_function_exists("${_name}" ${_prefix}${_combined_name}_WORKS)
     else()
@@ -1086,5 +1084,4 @@ if(NOT BLA_F95)
 endif()
 
 _add_blas_target()
-cmake_pop_check_state()
 set(CMAKE_FIND_LIBRARY_SUFFIXES ${_blas_ORIG_CMAKE_FIND_LIBRARY_SUFFIXES})