[C++] `ARROW_FLIGHT_SQL=ON` and `ARROW_BUILD_EXAMPLES=ON` miss gflags dependency

[kou]

Describe the bug, including details regarding any error messages, version, and platform.

This condition misses the case.

arrow/cpp/cmake_modules/ThirdpartyToolchain.cmake

Lines 1683 to 1686 in 6dfef94

	if(ARROW_BUILD_TESTS
	OR ARROW_BUILD_BENCHMARKS
	OR ARROW_BUILD_INTEGRATION
	OR ARROW_USE_GLOG)

Component(s)

C++

[raulcd]

Issue resolved by pull request 49542
#49542