configure.sh: prefer 'which' over 'hash'

hash may trigger a bashism warning; which is already depended on by this
script

Change-Id: Ibe0e7d1132d72f03aaf5b7d4c6180b59e92aceff

build/make/configure.sh

diff --git a/build/make/configure.sh b/build/make/configure.sh
index b305d33..8ea755a 100644
--- a/build/make/configure.sh
+++ b/build/make/configure.sh
@@ -1069,7 +1069,7 @@
           if enabled rvct; then
             # Check if we have CodeSourcery GCC in PATH. Needed for
             # libraries
-            hash arm-none-linux-gnueabi-gcc 2>&- || \
+            which arm-none-linux-gnueabi-gcc 2>&- || \
               die "Couldn't find CodeSourcery GCC from PATH"
 
             # Use armcc as a linker to enable translation of