Handle empty ldflags (#180)

Author: joaoubaldo

release.sh

@@ -61,10 +61,7 @@ if [ ${INPUT_GOOS} == 'windows' ]; then
 fi
 
 # prefix for ldflags
-LDFLAGS_PREFIX=''
-if [ ! -z "${INPUT_LDFLAGS}" ]; then
-  LDFLAGS_PREFIX="-ldflags"
-fi
+LDFLAGS_PREFIX='-ldflags'
 
 # fulfill GOAMD64 option
 if [ ! -z "${INPUT_GOAMD64}" ]; then