linker: get rid of the buddy allocator

Currently, the Android linker is placing shared libraries into
a well-known spot in memory.  This is interfering with the kernel's
ASLR support.

This change stops forcing non-prelinked libraries into a particular
address space.

Also, get rid of FLAG_PRELINKED.  As best I can tell, this flag
is never used.

Change-Id: I527af12fb54f821c2b5ca7693dbf63d022f8f4ae
diff --git a/linker/Android.mk b/linker/Android.mk
index abe5995..60f291c 100644
--- a/linker/Android.mk
+++ b/linker/Android.mk
@@ -8,8 +8,7 @@
 	linker_format.c \
 	rt.c \
 	dlfcn.c \
-	debugger.c \
-	ba.c
+	debugger.c
 
 ifeq ($(TARGET_ARCH),sh)
 # SH-4A series virtual address range from 0x00000000 to 0x7FFFFFFF.