Remote test for alloc extern_crate feature.

This functionality was removed in
45bf1ed1a1123122ded05ae2eedaf0f190e52726, but the test was left by
mistake.

src/test/run-make-fulldeps/alloc-extern-crates/Makefile

@@ -1,5 +0,0 @@
--include ../tools.mk
-
-all:
-	$(RUSTC) fakealloc.rs
-	$(RUSTC) --edition=2018 --crate-type=rlib ../../../../library/alloc/src/lib.rs --cfg feature=\"external_crate\" --extern external=$(TMPDIR)/$(shell $(RUSTC) --print file-names fakealloc.rs)

src/test/run-make-fulldeps/alloc-extern-crates/fakealloc.rs

@@ -1,25 +0,0 @@
-#![crate_type = "rlib"]
-#![no_std]
-
-#[inline]
-pub unsafe fn allocate(_size: usize, _align: usize) -> *mut u8 {
-    core::ptr::null_mut()
-}
-
-#[inline]
-pub unsafe fn deallocate(_ptr: *mut u8, _old_size: usize, _align: usize) { }
-
-#[inline]
-pub unsafe fn reallocate(_ptr: *mut u8, _old_size: usize, _size: usize, _align: usize) -> *mut u8 {
-    core::ptr::null_mut()
-}
-
-#[inline]
-pub unsafe fn reallocate_inplace(_ptr: *mut u8, old_size: usize, _size: usize,
-                                    _align: usize) -> usize { old_size }
-
-#[inline]
-pub fn usable_size(size: usize, _align: usize) -> usize { size }
-
-#[inline]
-pub fn stats_print() { }