Update C892FSP-K9.yaml

Fixed caps in slug

Author: harryajc

device-types/Cisco/C892FSP-K9.yaml

@@ -2,7 +2,7 @@
 manufacturer: Cisco
 model: Catalyst 892FSP-K9
 part_number: C892FSP-K9
-slug: cisco-C892fsp-k9
+slug: cisco-c892fsp-k9
 u_height: 1
 is_full_depth: false
 comment: '[Catalyst 892FSP-K9](https://www.cisco.com/c/en/us/products/collateral/routers/800-series-routers/data_sheet_c78-519930.html)'