regex: disambiguate builtin vs system pcre

src/CMakeLists.txt

@@ -314,7 +314,7 @@ ELSEIF(REGEX STREQUAL "regcomp")
 	SET(GIT_REGEX_REGCOMP 1)
 ELSEIF(REGEX STREQUAL "builtin")
 	ADD_FEATURE_INFO(regex ON "using bundled PCRE")
-	SET(GIT_REGEX_PCRE 1)
+	SET(GIT_REGEX_BUILTIN 1)
 
 	ADD_SUBDIRECTORY("${libgit2_SOURCE_DIR}/deps/pcre" "${libgit2_BINARY_DIR}/deps/pcre")
 	LIST(APPEND LIBGIT2_INCLUDES "${libgit2_SOURCE_DIR}/deps/pcre")

src/features.h.in

@@ -19,6 +19,7 @@
 #cmakedefine GIT_REGEX_REGCOMP_L
 #cmakedefine GIT_REGEX_REGCOMP
 #cmakedefine GIT_REGEX_PCRE
+#cmakedefine GIT_REGEX_BUILTIN 1
 
 #cmakedefine GIT_SSH 1
 #cmakedefine GIT_SSH_MEMORY_CREDENTIALS 1

src/posix_regex.h

@@ -15,7 +15,7 @@
  * compatible implementation.
  */
 
-#ifdef GIT_REGEX_PCRE
+#ifdef GIT_REGEX_BUILTIN
 
 # include "pcreposix.h"