Kernel/Storage: Remove redundant reference to a controller in IDEChannel

IDEChannel which is an ATAPort derived class holded a NonnullRefPtr to a
parent IDEController, although we can easily defer the usage of it to
not be in the IDEChannel code at all, so it allows to keep NonnullRefPtr
to the parent ATAController in the ATAPort base class and only there.

Kernel/Storage/ATA/GenericIDE/Channel.cpp

@@ -122,7 +122,6 @@ UNMAP_AFTER_INIT IDEChannel::IDEChannel(IDEController const& controller, u8 irq,
     , IRQHandler(irq)
     , m_channel_type(type)
     , m_io_group(io_group)
-    , m_parent_controller(controller)
 {
 }
 
@@ -131,7 +130,6 @@ UNMAP_AFTER_INIT IDEChannel::IDEChannel(IDEController const& controller, IOAddre
     , IRQHandler(type == ChannelType::Primary ? PATA_PRIMARY_IRQ : PATA_SECONDARY_IRQ)
     , m_channel_type(type)
     , m_io_group(io_group)
-    , m_parent_controller(controller)
 {
 }
 

Kernel/Storage/ATA/GenericIDE/Channel.h

@@ -165,6 +165,5 @@ private:
     bool m_interrupts_enabled { true };
 
     IOAddressGroup m_io_group;
-    NonnullRefPtr<IDEController> m_parent_controller;
 };
 }