Upgrade vendored lmdb to version 0.9.30

Among other changes, `lmdb-0.9.30` brings in an important bugfix from
https://git.openldap.org/openldap/openldap/-/merge_requests/563, which avoids a
nasty linker error on ARM64 macOS (see
GaloisInc/saw-script#2084 for an example of this
error in the wild).

lmdb/README.md

@@ -7,7 +7,7 @@ longer maintained, so this fork makes a number of small improvements, including:
 
 * By default, this statically links against a bundled copy of the `lmdb` C
   library, which avoids the need for users to install `lmdb` themselves.
-  Currently, version 0.9.29 of `lmdb` is bundled. This behavior can be toggled
+  Currently, version 0.9.30 of `lmdb` is bundled. This behavior can be toggled
   by opting into the `-fpkg-config` `cabal` flag, which instead uses the
   `pkg-config` tool to locate a foreign `lmdb` library installed on your
   system.

lmdb/cbits/lmdb.h

@@ -200,7 +200,7 @@ typedef int mdb_filehandle_t;
 /** Library minor version */
 #define MDB_VERSION_MINOR	9
 /** Library patch version */
-#define MDB_VERSION_PATCH	29
+#define MDB_VERSION_PATCH	30
 
 /** Combine args a,b,c into a single integer for easy version comparisons */
 #define MDB_VERINT(a,b,c)	(((a) << 24) | ((b) << 16) | (c))
@@ -210,7 +210,7 @@ typedef int mdb_filehandle_t;
 	MDB_VERINT(MDB_VERSION_MAJOR,MDB_VERSION_MINOR,MDB_VERSION_PATCH)
 
 /** The release date of this library version */
-#define MDB_VERSION_DATE	"March 16, 2021"
+#define MDB_VERSION_DATE	"February 8, 2023"
 
 /** A stringifier for the version info */
 #define MDB_VERSTR(a,b,c,d)	"LMDB " #a "." #b "." #c ": (" d ")"