Fix a few bionic test failures caused by hwasan global instrumentation.

The call to the load hook needs to be moved before the call to link_image()
because the latter calls ifunc resolvers which might access global
variables. This fixes a bunch of ifunc tests.

The dlfcn.segment_gap test is currently failing. One problem is that the name
of the .bss.end_of_gap section changes as a result of global instrumentation.
Add some wildcards in so that we match both names. The other problem seems
to be the same as b/139089152.

It turns out that we need to untag pointers in a few more places. Since we have
quite a few of these now it seems worth creating a function for it.

Test: bionic-unit-tests
Change-Id: I44e2b0904faacdda7cc0c5e844ffc09de01dea2d
diff --git a/libc/private/bionic_macros.h b/libc/private/bionic_macros.h
index 4800e3a..13934e5 100644
--- a/libc/private/bionic_macros.h
+++ b/libc/private/bionic_macros.h
@@ -87,3 +87,12 @@
 #else
 #define __BIONIC_FALLTHROUGH
 #endif
+
+template <typename T>
+static inline T* untag_address(T* p) {
+#if defined(__aarch64__)
+  return reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(p) & ((1ULL << 56) - 1));
+#else
+  return p;
+#endif
+}