fix(ci): correct typo in poetry memmap invocation

The variable `tf_build_path` does not exist; the correct name for the
build root is `tf_build_root`. Additionally, the memmap tool invocation
should be non-fatal, allowing errors to be ignored.

Signed-off-by: Harrison Mutai <harrison.mutai@arm.com>
Change-Id: Ibc68ae63ec2276b1f591096cffe6eeec388e525d
diff --git a/script/build_package.sh b/script/build_package.sh
index 6b777d7..d91ef1d 100755
--- a/script/build_package.sh
+++ b/script/build_package.sh
@@ -581,7 +581,7 @@
 		$build_targets 3>&1 &>>"$build_log" || fail_build
 
         if [ "$build_targets" != "doc" ]; then
-                poetry run memory -sr "$tf_build_path" 2>&1 | tee -a "$build_log"
+                (poetry run memory -sr "$tf_build_root" 2>&1 || true) | tee -a "$build_log"
         fi
 	)
 }