[Fix] `nvm_get_arch`: suppress error output if `/sbin` does not exist

Introduced by #2469

nvm.sh

@@ -1818,7 +1818,7 @@ nvm_get_arch() {
   esac
 
   # If running a 64bit ARM kernel but a 32bit ARM userland, change ARCH to 32bit ARM (armv7l)
-  L=$(ls -dl /sbin/init) #                                         if /sbin/init is 32bit executable
+  L=$(ls -dl /sbin/init 2>/dev/null) # if /sbin/init is 32bit executable
   if [ "$(uname)" = "Linux" ] && [ "${NVM_ARCH}" = arm64 ] && [ "$(od -An -t x1 -j 4 -N 1 "${L#*-> }")" = ' 01' ]; then
     NVM_ARCH=armv7l
     HOST_ARCH=armv7l