librecovery: Remove -Wno-unused-parameter and add -Wall.

Test: mmma bootable/recovery
Change-Id: I5598d32bebb9dbda4a183a1502e0b7dc4918392e
diff --git a/install.cpp b/install.cpp
index e5a59b8..e945d13 100644
--- a/install.cpp
+++ b/install.cpp
@@ -211,7 +211,7 @@
   return 0;
 }
 
-int update_binary_command(const std::string& path, ZipArchiveHandle zip, int retry_count,
+int update_binary_command(const std::string& path, ZipArchiveHandle zip, int /* retry_count */,
                           int status_fd, std::vector<std::string>* cmd) {
   CHECK(cmd != nullptr);
   int ret = check_newer_ab_build(zip);