configure: Move optflags checks to a more sensible place

configure

@@ -4926,6 +4926,9 @@ check_optflags(){
     enabled lto && check_ldflags "$@"
 }
 
+check_optflags $optflags
+check_optflags -fno-math-errno
+check_optflags -fno-signed-zeros
 
 if enabled lto; then
     test "$cc_type" != "$ld_type" && die "LTO requires same compiler and linker"
@@ -4933,10 +4936,6 @@ if enabled lto; then
     check_ldflags -flto $cpuflags
 fi
 
-check_optflags $optflags
-check_optflags -fno-math-errno
-check_optflags -fno-signed-zeros
-
 if enabled icc; then
     # Just warnings, no remarks
     check_cflags -w1