Fix LLVMBuild.txt typo. NFC

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299373 91177308-0d34-0410-b5e6-96231b3b80d8

docs/LLVMBuild.rst

@@ -54,7 +54,7 @@ handled by another build system (See: :doc:`CMake <CMake>`).
 The build system implementation will load the relevant contents of the
 LLVMBuild files and use that to drive the actual project build.
 Typically, the build system will only need to load this information at
-"configure" time, and use it to generative native information. Build
+"configure" time, and use it to generate native information. Build
 systems will also handle automatically reconfiguring their information
 when the contents of the ``LLVMBuild.txt`` files change.