Fixed build issue with apps/exit.c

Signed-off-by: Nigel Croxon <ncroxon@redhat.com>

apps/Makefile

@@ -60,7 +60,7 @@ LOADLIBES	+= -T $(LDSCRIPT)
 
 TARGET_APPS = t.efi t2.efi t3.efi t4.efi t5.efi t6.efi \
 	      printenv.efi t7.efi t8.efi tcc.efi modelist.efi \
-	      route80h.efi drv0_use.efi AllocPages.efi \
+	      route80h.efi drv0_use.efi AllocPages.efi exit.efi \
 	      FreePages.efi setjmp.efi debughook.efi debughook.efi.debug
 TARGET_BSDRIVERS = drv0.efi
 TARGET_RTDRIVERS =