Fix iosbuild.sh: outdated reference to ios-version.sh

File was removed in b29ebfe91c643b4bab1f24c2b55bf0a5a83cb825 but a
reference was missed.

Change-Id: I7a3d81ab196a70cb5691331705f956cc7dc9bb2a

build/make/iosbuild.sh

diff --git a/build/make/iosbuild.sh b/build/make/iosbuild.sh
index 96dc6cc..c703f22 100755
--- a/build/make/iosbuild.sh
+++ b/build/make/iosbuild.sh
@@ -347,10 +347,11 @@
 
 if [ "$ENABLE_SHARED" = "yes" ]; then
   IOS_VERSION_OPTIONS="--enable-shared"
+  IOS_VERSION_MIN="8.0"
 else
   IOS_VERSION_OPTIONS=""
+  IOS_VERSION_MIN="6.0"
 fi
-IOS_VERSION_MIN=$("${SCRIPT_DIR}/ios-version.sh" ${IOS_VERSION_OPTIONS})
 
 if [ "${VERBOSE}" = "yes" ]; then
 cat << EOF