Fix:Mismatch of IF and ENDIF expressions when compiling with clang

- When bmcweb is compiled with clang compiler, Cmake throws a warning
  as the expressions of IF and ENDIF are mismatched.
- This commit would fix the warning.

Tested By:
- When cmake is triggered with clang compiler, the warning goes away.

Signed-off-by: Manojkiran Eda <manojkiran.eda@gmail.com>
Change-Id: I836df40b80b7a230a3d24f51e741ba88e6652b9c