<bionic/macros.h>: replace align_up()/align_down() with clang's builtins.

Change-Id: If39cf028e9a22fc2008ee9d1ba683a4d0d038325
diff --git a/linker/linker_note_gnu_property.cpp b/linker/linker_note_gnu_property.cpp
index 082a604..d221b8d 100644
--- a/linker/linker_note_gnu_property.cpp
+++ b/linker/linker_note_gnu_property.cpp
@@ -137,7 +137,7 @@
     // Loop on program property array.
     const ElfW(Prop)* property = reinterpret_cast<const ElfW(Prop)*>(&note_nhdr->n_desc[offset]);
     const ElfW(Word) property_size =
-        align_up(sizeof(ElfW(Prop)) + property->pr_datasz, sizeof(ElfW(Addr)));
+        __builtin_align_up(sizeof(ElfW(Prop)) + property->pr_datasz, sizeof(ElfW(Addr)));
     if ((note_nhdr->nhdr.n_descsz - offset) < property_size) {
       DL_ERR_AND_LOG(
           "\"%s\" .note.gnu.property: property descriptor size is "