target: fix memory leak in handle_target_write_memory()

Commit f55ec6d ("target: rewrite command 'write_memory' as
COMMAND_HANDLER") adds a new return statement without freeing the
allocated buffer.

Add the needed free().

Fixes: f55ec6d ("target: rewrite command 'write_memory' as COMMAND_HANDLER")
Change-Id: I676d658118b32f4d7cc71eda3436bb52f1966cd8
Signed-off-by: Antonio Borneo <[email protected]>
Reviewed-on: https://review.openocd.org/c/openocd/+/8822
Tested-by: jenkins

Author: borneoa

src/target/target.c

@@ -4608,6 +4608,7 @@ COMMAND_HANDLER(handle_target_write_memory)
 			int jimretval = Jim_GetWide(CMD_CTX->interp, tmp, &element_wide);
 			if (jimretval != JIM_OK) {
 				command_print(CMD, "invalid value \"%s\"", Jim_GetString(tmp, NULL));
+				free(buffer);
 				return ERROR_COMMAND_ARGUMENT_INVALID;
 			}