scripts: apply-renames: Update default clang version to 18

clang 18.1.8 is currently installed in the OpenBMC CI container.
Changing the default saves having to explicitly invoke `scripts/
apply-renames` with `CLANG_VERSION=18`.

Change-Id: I2f0ff5baf485a34089dc663cb5870efa36f3c3c6
Signed-off-by: Andrew Jeffery <andrew@codeconstruct.com.au>
diff --git a/scripts/apply-renames b/scripts/apply-renames
index 8f6e111..3bd10eb 100755
--- a/scripts/apply-renames
+++ b/scripts/apply-renames
@@ -11,7 +11,7 @@
 : "${LIBPLDM_ROOT:="${ABSPATH%scripts/apply-renames}"}"
 
 # Deal with clang including its version in all the tool names
-: "${CLANG_VERSION:=17}"
+: "${CLANG_VERSION:=18}"
 : "${CLANG_RENAME:="$(command -v clang-rename-"${CLANG_VERSION}")"}"
 : "${CLANG_APPLY_REPLACEMENTS:="$(command -v clang-apply-replacements-"${CLANG_VERSION}")"}"