pam: fix pam_unix autohentication failures when ran as user

Commit d0c42dfa "pam: bind Linux-PAM locales from pam-specific folder
(upstream patch)" added autoreconfHook269 into one of the postPatch
phases.

This clobbered the change applied by `suid-wrapper-path.patch` as it was
patching Makefile.in.

As a result `nixosTests.sway` test started failing as:

    check pass; user unknown

Running `swaylock` on real system exhibited the same result.

As `suid-wrapper-path.patch` is clobbered we were running non-suid
version of `unix_chkpwd`:

    /nix/store/...-linux-pam-1.5.2/sbin/unix_chkpwd

instead of SUID-wrapped

    /run/wrappers/bin/unix_chkpw

The fix is trivial: move the patch from auto-generated file to
`Makefile.am`.

Discovered-by: Yureka

pkgs/os-specific/linux/pam/default.nix

@@ -29,7 +29,8 @@ stdenv.mkDerivation rec {
   outputs = [ "out" "doc" "man" /* "modules" */ ];
 
   depsBuildBuild = [ buildPackages.stdenv.cc ];
-  # autoreconfHook269 is needed for `bind-locales.patch` above
+  # autoreconfHook269 is needed for `suid-wrapper-path.patch` and
+  # `bind-locales.patch` above.
   # pkg-config-unwrapped is needed for `AC_CHECK_LIB` and `AC_SEARCH_LIBS`
   nativeBuildInputs = [ flex autoreconfHook269 pkg-config-unwrapped ]
     ++ lib.optional stdenv.buildPlatform.isDarwin gettext;

pkgs/os-specific/linux/pam/suid-wrapper-path.patch

@@ -1,6 +1,6 @@
 It needs the SUID version during runtime, and that can't be in /nix/store/**
---- a/modules/pam_unix/Makefile.in
-+++ b/modules/pam_unix/Makefile.in
-@@ -651 +651 @@
+--- a/modules/pam_unix/Makefile.am
++++ b/modules/pam_unix/Makefile.am
+@@ -21 +21 @@
 -	-DCHKPWD_HELPER=\"$(sbindir)/unix_chkpwd\" \
 +	-DCHKPWD_HELPER=\"/run/wrappers/bin/unix_chkpwd\" \