Fix warnings generated by clang-cl.

There were a couple of real bugs here regarding error checking and
signed/unsigned comparisons, but mostly these were just noise.

There was one class of bugs fixed here which is particularly
annoying, dealing with MSVC's non-standard behavior regarding
the underlying type of enums.  See the comment in
lldb-enumerations.h for details.  In short, from now on please use
FLAGS_ENUM and FLAGS_ANONYMOUS_ENUM when defining enums which
contain values larger than can fit into a signed integer.

llvm-svn: 233943
diff --git a/lldb/source/Host/common/Socket.cpp b/lldb/source/Host/common/Socket.cpp
index 3bcd934..ff1ca7d 100644
--- a/lldb/source/Host/common/Socket.cpp
+++ b/lldb/source/Host/common/Socket.cpp
@@ -704,7 +704,7 @@
 uint16_t Socket::GetLocalPortNumber(const NativeSocket& socket)
 {
     // We bound to port zero, so we need to figure out which port we actually bound to
-    if (socket >= 0)
+    if (socket != kInvalidSocketValue)
     {
         SocketAddress sock_addr;
         socklen_t sock_addr_len = sock_addr.GetMaxLength ();
@@ -723,7 +723,7 @@
 std::string  Socket::GetLocalIPAddress () const
 {
     // We bound to port zero, so we need to figure out which port we actually bound to
-    if (m_socket >= 0)
+    if (m_socket != kInvalidSocketValue)
     {
         SocketAddress sock_addr;
         socklen_t sock_addr_len = sock_addr.GetMaxLength ();
@@ -735,7 +735,7 @@
 
 uint16_t Socket::GetRemotePortNumber () const
 {
-    if (m_socket >= 0)
+    if (m_socket != kInvalidSocketValue)
     {
         SocketAddress sock_addr;
         socklen_t sock_addr_len = sock_addr.GetMaxLength ();
@@ -748,7 +748,7 @@
 std::string Socket::GetRemoteIPAddress () const
 {
     // We bound to port zero, so we need to figure out which port we actually bound to
-    if (m_socket >= 0)
+    if (m_socket != kInvalidSocketValue)
     {
         SocketAddress sock_addr;
         socklen_t sock_addr_len = sock_addr.GetMaxLength ();