only run `pass-by-value-abi` on 64-bit windows

the 32-bit variant differs only in the alignment/size, and I can't test it locally

tests/ui/c-variadic/pass-by-value-abi.aarch64.stderr

diff --git a/tests/ui/c-variadic/pass-by-value-abi.aarch64.stderr b/tests/ui/c-variadic/pass-by-value-abi.aarch64.stderr
index fe11c42..a86b28d 100644
--- a/tests/ui/c-variadic/pass-by-value-abi.aarch64.stderr
+++ b/tests/ui/c-variadic/pass-by-value-abi.aarch64.stderr
@@ -71,7 +71,7 @@
            conv: C,
            can_unwind: false,
        }
-  --> $DIR/pass-by-value-abi.rs:26:1
+  --> $DIR/pass-by-value-abi.rs:27:1
    |
 LL | pub extern "C" fn take_va_list(_: VaList<'_>) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

tests/ui/c-variadic/pass-by-value-abi.rs

diff --git a/tests/ui/c-variadic/pass-by-value-abi.rs b/tests/ui/c-variadic/pass-by-value-abi.rs
index b65442a..1e39350 100644
--- a/tests/ui/c-variadic/pass-by-value-abi.rs
+++ b/tests/ui/c-variadic/pass-by-value-abi.rs
@@ -12,9 +12,10 @@
 //@ [aarch64] ignore-windows
 //@ [aarch64] ignore-apple
 //@ [aarch64] ignore-uefi
-// Windows dosen't use `#[rustc_pass_indirectly_in_non_rustic_abis]` and is tested in CI, so is here
+// Windows doesn't use `#[rustc_pass_indirectly_in_non_rustic_abis]` and is tested in CI, so is here
 // for comparison.
 //@ [win] only-windows
+//@ [win] only-x86_64
 
 #![feature(rustc_attrs, c_variadic)]
 #![crate_type = "lib"]

tests/ui/c-variadic/pass-by-value-abi.win.stderr

diff --git a/tests/ui/c-variadic/pass-by-value-abi.win.stderr b/tests/ui/c-variadic/pass-by-value-abi.win.stderr
index e844308..8ff9396 100644
--- a/tests/ui/c-variadic/pass-by-value-abi.win.stderr
+++ b/tests/ui/c-variadic/pass-by-value-abi.win.stderr
@@ -74,7 +74,7 @@
            conv: C,
            can_unwind: false,
        }
-  --> $DIR/pass-by-value-abi.rs:26:1
+  --> $DIR/pass-by-value-abi.rs:27:1
    |
 LL | pub extern "C" fn take_va_list(_: VaList<'_>) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

tests/ui/c-variadic/pass-by-value-abi.x86_64.stderr

diff --git a/tests/ui/c-variadic/pass-by-value-abi.x86_64.stderr b/tests/ui/c-variadic/pass-by-value-abi.x86_64.stderr
index 73f1ccd..aafe89d 100644
--- a/tests/ui/c-variadic/pass-by-value-abi.x86_64.stderr
+++ b/tests/ui/c-variadic/pass-by-value-abi.x86_64.stderr
@@ -71,7 +71,7 @@
            conv: C,
            can_unwind: false,
        }
-  --> $DIR/pass-by-value-abi.rs:26:1
+  --> $DIR/pass-by-value-abi.rs:27:1
    |
 LL | pub extern "C" fn take_va_list(_: VaList<'_>) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -151,7 +151,7 @@
            ),
            can_unwind: false,
        }
-  --> $DIR/pass-by-value-abi.rs:36:1
+  --> $DIR/pass-by-value-abi.rs:37:1
    |
 LL | pub extern "sysv64" fn take_va_list_sysv64(_: VaList<'_>) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -231,7 +231,7 @@
            ),
            can_unwind: false,
        }
-  --> $DIR/pass-by-value-abi.rs:43:1
+  --> $DIR/pass-by-value-abi.rs:44:1
    |
 LL | pub extern "win64" fn take_va_list_win64(_: VaList<'_>) {}
    | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^