MCP uart log file name require a minor fix (css-mcp_uar0 -> css-mcp_uart0
and css-mcp_uar1 -> css-mcp_uart1)

Change-Id: If0f2dc5be17b99d69a93ca8d4d2ce58eaf3a21d8
Signed-off-by: Thomas Abraham <thomas.abraham@arm.com>