cmake: fix warning for later CMake versions by rizsotto · Pull Request #221

cmake: fix warning for later CMake versions by rizsotto · Pull Request #221 · librsync/librsync

When building this project with CMake (version 3.20.5), I got the following error message:

-- Found ZLIB: /usr/lib64/libz.so (found version "1.2.11") 
-- ZLIB_INCLUDE_DIRS  = /usr/include
-- ZLIB_LIBRARIES = /usr/lib64/libz.so
CMake Warning (dev) at /usr/share/cmake/Modules/FindPackageHandleStandardArgs.cmake:438 (message):
  The package name passed to `find_package_handle_standard_args` (LIBB2) does
  not match the name of the calling package (libb2).  This can lead to
  problems in calling code that expects `find_package` result variables
  (e.g., `_FOUND`) to follow a certain pattern.
Call Stack (most recent call first):
  cmake/Findlibb2.cmake:16 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
  CMakeLists.txt:183 (find_package)
This warning is for project developers.  Use -Wno-dev to suppress it.

-- Found LIBB2: /usr/lib64/libb2.so  
-- LIBB2_INCLUDE_DIRS  = /usr/include
-- LIBB2_LIBRARIES = /usr/lib64/libb2.so

To fix it, I've just followed the error message instruction and renamed the cmake/Findlibb2.cmake to cmake/FindLIBB2.cmake. (Plus, I've converted the CMake commands to lowercase to match with the rest of the project.)