fix regression that made shared libs crash on arm

crt/arm/crti.s

@@ -5,6 +5,8 @@ _init:
 
 .weak __fini_array_start
 .weak __fini_array_end
+.hidden __fini_array_start
+.hidden __fini_array_end
 
 .section .fini
 .global _fini

crt/arm/crtn.s

@@ -1,5 +1,7 @@
 .weak __init_array_start
 .weak __init_array_end
+.hidden __init_array_start
+.hidden __init_array_end
 
 .section .init
 	adr lr, 1f