libpthread/nptl_db: define NOT_IN_libc

NPTL build for x86_64 failed with

  LD libthread_db-0.9.32-git.so
  .../ld: libpthread/nptl_db/libthread_db_so.a(td_ta_event_getmsg.oS): relocation R_X86_64_PC32 against undefined symbol `__GI_memset' can not be used when making a shared object; recompile with -fPIC

Signed-off-by: Roman I Khimov <khimov@altell.ru>
Signed-off-by: Austin Foxley <austinf@cetoncorp.com>

libpthread/nptl_db/Makefile.in

@@ -10,7 +10,7 @@ subdirs += libpthread/nptl/nptl_db
 # Get the thread include dependencies and shared object name
 CFLAGS-nptl_db := -DLIBPTHREAD_SO="\"libpthread.so.$(ABI_VERSION)\""
 CFLAGS-nptl_db += -I$(top_srcdir)libpthread/nptl -D_GNU_SOURCE
-CFLAGS-nptl_db += -DIS_IN_libthread_db=1 -std=gnu99 -I$(top_srcdir)ldso/include
+CFLAGS-nptl_db += -DIS_IN_libthread_db=1 -DNOT_IN_libc -std=gnu99 -I$(top_srcdir)ldso/include
 
 LDFLAGS-libthread_db.so := $(LDFLAGS_NOSTRIP) -s --warn-unresolved-symbols