Remove outdated restriction on -Werror on cosmocc

This was a good idea back when we were only using it to build various
open source projects. However it no longer makes sense that many more
people are depending on cosmocc, to develop new software. Our tooling
shouldn't be making these kinds of decisions for the user.

tool/cosmocc/bin/cosmocc

@@ -184,11 +184,6 @@ for x; do
     # no support for position independent executables
     # https://github.com/jart/cosmopolitan/issues/1126
     continue
-  elif [ x"$x" = x"-Werror" ] || \
-       [ x"$x" = x"-pedantic-errors" ]; then
-    # this toolchain is intended for building other people's code
-    # elevating warnings into errors, should only be done by devs
-    continue
   elif [ x"$x" = x"-static-libgcc" ] || \
        [ x"$x" = x"-shared-libgcc" ]; then
     # cosmopolitan.a always has llvm compiler runtime static code

tool/cosmocc/bin/cosmocross

@@ -165,11 +165,6 @@ for x; do
     # information."
     set -- "$@" -momit-leaf-frame-pointer -foptimize-sibling-calls
     continue
-  elif [ x"$x" != x"${x#-Werror}" ] || \
-       [ x"$x" = x"-pedantic-errors" ]; then
-    # this toolchain is intended for building other people's code
-    # elevating warnings into errors, should only be done by devs
-    continue
   elif [ x"$x" = x"-dumpversion" ]; then
     echo $GCC_VERSION
     exit 0