Align on a single CMake style.

We currently write a mix of "if (FOO)" and "if(FOO)". While the former looks
more like a usual language, CMake believes everything, even "if" and "else", is
just a really really funny function call (a "command").

We should pick something for consistency. Upstream CMake writes "if(FOO)", so
go with that one.

Change-Id: I67e0eb650a52670110b417312a362c9f161c8721
Reviewed-on: https://boringssl-review.googlesource.com/30807
Reviewed-by: Adam Langley <agl@google.com>

ssl/CMakeLists.txt

@@ -54,7 +54,7 @@ add_executable(
 )
 
 target_link_libraries(ssl_test ssl crypto boringssl_gtest)
-if (WIN32)
+if(WIN32)
   target_link_libraries(ssl_test ws2_32)
 endif()
 add_dependencies(all_tests ssl_test)