oid: Explicitly include `oid.h` for the inlined CMP

src/attr.c

 #include "repository.h"
 #include "fileops.h"
 #include "config.h"
+#include "git2/oid.h"
 #include <ctype.h>
 
 GIT__USE_STRMAP;

src/cache.c

@@ -11,6 +11,7 @@
 #include "thread-utils.h"
 #include "util.h"
 #include "cache.h"
+#include "git2/oid.h"
 
 int git_cache_init(git_cache *cache, size_t size, git_cached_obj_freeptr free_ptr)
 {

src/diff.c

@@ -6,6 +6,7 @@
  */
 #include "common.h"
 #include "git2/diff.h"
+#include "git2/oid.h"
 #include "diff.h"
 #include "fileops.h"
 #include "config.h"

src/diff_output.c

@@ -8,6 +8,7 @@
 #include "git2/diff.h"
 #include "git2/attr.h"
 #include "git2/blob.h"
+#include "git2/oid.h"
 #include "xdiff/xdiff.h"
 #include <ctype.h>
 #include "diff.h"

src/index.c

@@ -14,6 +14,7 @@
 #include "tree-cache.h"
 #include "hash.h"
 #include "git2/odb.h"
+#include "git2/oid.h"
 #include "git2/blob.h"
 #include "git2/config.h"
 

src/odb.c

@@ -14,6 +14,7 @@
 #include "delta-apply.h"
 
 #include "git2/odb_backend.h"
+#include "git2/oid.h"
 
 #define GIT_ALTERNATES_FILE "info/alternates"
 

src/refs.c

@@ -14,6 +14,7 @@
 
 #include <git2/tag.h>
 #include <git2/object.h>
+#include <git2/oid.h>
 
 GIT__USE_STRMAP;
 

src/remote.c

@@ -7,6 +7,7 @@
 
 #include "git2/config.h"
 #include "git2/types.h"
+#include "git2/oid.h"
 
 #include "config.h"
 #include "repository.h"