refactor(base): remove str_replace from dracut-lib.sh

Remove duplicate implementation of `str_replace` to follow-up
commit 148e420

Author: LaszloGombos

modules.d/99base/dracut-lib.sh

@@ -103,26 +103,6 @@ vinfo() {
     done
 }
 
-# replaces all occurrences of 'search' in 'str' with 'replacement'
-#
-# str_replace str search replacement
-#
-# example:
-# str_replace '  one two  three  ' ' ' '_'
-str_replace() {
-    local in="$1"
-    local s="$2"
-    local r="$3"
-    local out=''
-
-    while strstr "${in}" "$s"; do
-        chop="${in%%"$s"*}"
-        out="${out}${chop}$r"
-        in="${in#*"$s"}"
-    done
-    echo "${out}${in}"
-}
-
 killall_proc_mountpoint() {
     local _pid
     local _killed=0