Fix two typos

Author: seisman

cmake/ConfigUserAdvancedTemplate.cmake

@@ -195,7 +195,7 @@
 # List extra sub-dirs of 'src' with a CMakeLists.txt to build custom modules
 # that link against the full gmt libs. (For building codes that only need the GMT API,
 # see the https://github.com/GenericMappingTools/custom-supplements project).
-# These supplemental modules can be built into seperate libraries.
+# These supplemental modules can be built into separate libraries.
 #set (SUPPL_EXTRA_DIRS newsuppl1 newsuppl2 ...)
 
 # Directory in which to install the release sources per default

cmake/modules/GmtHelperMacros.cmake

@@ -93,7 +93,7 @@ if(NOT DEFINED _GMT_HELPER_MACROS_CMAKE_)
 			get_directory_property (_files DIRECTORY ${_dir} DEFINITION ${VAR_NAME})
 			foreach (_file ${_files})
 				if (IS_ABSOLUTE ${_file})
-					# don't prepand name if is an absolute path
+					# don't prepend name if is an absolute path
 					list (APPEND ${VARIABLE} "${_file}")
 				else (IS_ABSOLUTE ${_file})
 					# prepend dirname