auth_algo: Remove unused variables

Since the userName variable was declared in[1] and deprecated in[2],
this commit removes the deprecated variable.

[1]: https://gerrit.openbmc.org/c/openbmc/phosphor-net-ipmid/+/9643
[2]: https://gerrit.openbmc.org/c/openbmc/phosphor-net-ipmid/+/13094/7/command/rakp12.cpp#b66

Signed-off-by: George Liu <liuxiwei@ieisystem.com>
Change-Id: Ia606607ae49e1f1923eae792a0f178fab52bbc3f
diff --git a/auth_algo.cpp b/auth_algo.cpp
index 40d277f..e686aeb 100644
--- a/auth_algo.cpp
+++ b/auth_algo.cpp
@@ -14,8 +14,6 @@
 namespace rakp_auth
 {
 
-const std::string userName = "admin";
-
 std::vector<uint8_t>
     AlgoSHA1::generateHMAC(const std::vector<uint8_t>& input) const
 {
diff --git a/auth_algo.hpp b/auth_algo.hpp
index f940370..7b12eff 100644
--- a/auth_algo.hpp
+++ b/auth_algo.hpp
@@ -15,7 +15,6 @@
 constexpr size_t USER_KEY_MAX_LENGTH = 20;
 constexpr size_t BMC_RANDOM_NUMBER_LEN = 16;
 constexpr size_t REMOTE_CONSOLE_RANDOM_NUMBER_LEN = 16;
-extern const std::string userName;
 
 /**
  * @enum RAKP Authentication Algorithms