shellcheck: add ignore for files currently failing

Soon shellcheck will be enabled by default on all repositories.
Add the currently failing files to the .shellcheck-ignore so the
repository continues to pass CI in its current state.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ie026586e0c372f9a9e36a8167863b6cc2a2f0bb3
diff --git a/.shellcheck-ignore b/.shellcheck-ignore
new file mode 100644
index 0000000..5d4635a
--- /dev/null
+++ b/.shellcheck-ignore
@@ -0,0 +1,10 @@
+bbdbg/bbdbg
+cla-signers/update-cla.sh
+ddconvnotrunc/ddconvnotrunc
+ipkdbg/build-opkg
+overlay/overlay
+pldm/pdrdump.sh
+prepare-emmc-qemu/prepare-emmc-qemu
+reboot/reboot.sh
+tracing/trace
+witherspoon-debug/debug