Remove ota_close(int) and ota_fclose(FILE*).

We should always use unique_fd or unique_file to hold the FD or FILE*
pointer when opening via ota_(f)open functions.

This CL avoids accidentally closing raw FDs or FILE* pointers that are
managed by unique_fd/unique_file.

Test: recovery_component_test passes.
Change-Id: If58eb8b5c5da507563f85efd5d56276472a1c957
diff --git a/applypatch/applypatch.cpp b/applypatch/applypatch.cpp
index 0250407..95389da 100644
--- a/applypatch/applypatch.cpp
+++ b/applypatch/applypatch.cpp
@@ -66,7 +66,7 @@
   }
 
   std::vector<unsigned char> data(file->st.st_size);
-  std::unique_ptr<FILE, int (*)(FILE*)> f(ota_fopen(filename, "rb"), ota_fclose);
+  unique_file f(ota_fopen(filename, "rb"));
   if (!f) {
     printf("failed to open \"%s\": %s\n", filename, strerror(errno));
     return -1;
@@ -118,7 +118,7 @@
   std::sort(pairs.begin(), pairs.end());
 
   const char* partition = pieces[1].c_str();
-  std::unique_ptr<FILE, int (*)(FILE*)> dev(ota_fopen(partition, "rb"), ota_fclose);
+  unique_file dev(ota_fopen(partition, "rb"));
   if (!dev) {
     printf("failed to open emmc partition \"%s\": %s\n", partition, strerror(errno));
     return -1;