[windows] Use windows.NewLazySystemDLL to (possibly) prevent DLL hijacking

Might be useless because of https://docs.microsoft.com/en-us/windows/desktop/dlls/dynamic-link-library-search-order#search-order-for-desktop-applications
but better be safe than sorry.

Ref: https://github.com/shirou/gopsutil/issues/570#issuecomment-413951653

internal/common/common_windows.go

@@ -47,10 +47,10 @@ const (
 )
 
 var (
-	Modkernel32 = windows.NewLazyDLL("kernel32.dll")
+	Modkernel32 = windows.NewLazySystemDLL("kernel32.dll")
-	ModNt       = windows.NewLazyDLL("ntdll.dll")
+	ModNt       = windows.NewLazySystemDLL("ntdll.dll")
-	ModPdh      = windows.NewLazyDLL("pdh.dll")
+	ModPdh      = windows.NewLazySystemDLL("pdh.dll")
-	ModPsapi    = windows.NewLazyDLL("psapi.dll")
+	ModPsapi    = windows.NewLazySystemDLL("psapi.dll")
 
 	ProcGetSystemTimes           = Modkernel32.NewProc("GetSystemTimes")
 	ProcNtQuerySystemInformation = ModNt.NewProc("NtQuerySystemInformation")

net/net_windows.go

@@ -13,7 +13,7 @@ import (
 )
 
 var (
-	modiphlpapi             = windows.NewLazyDLL("iphlpapi.dll")
+	modiphlpapi             = windows.NewLazySystemDLL("iphlpapi.dll")
 	procGetExtendedTCPTable = modiphlpapi.NewProc("GetExtendedTcpTable")
 	procGetExtendedUDPTable = modiphlpapi.NewProc("GetExtendedUdpTable")
 )

process/process_windows.go

@@ -25,7 +25,7 @@ const (
 )
 
 var (
-	modpsapi                 = windows.NewLazyDLL("psapi.dll")
+	modpsapi                 = windows.NewLazySystemDLL("psapi.dll")
 	procGetProcessMemoryInfo = modpsapi.NewProc("GetProcessMemoryInfo")
 )