Kernel: Remove SpinLock from Pipe

Pipe already is using lock on the inode. If you read from pipe when
there was no data, pipe blocked indefinately since writes were blocked
by Inode::m_lock.

kernel/include/kernel/FS/Pipe.h

@@ -48,7 +48,6 @@ namespace Kernel
 		timespec m_mtime {};
 		timespec m_ctime {};
 		BAN::Vector<uint8_t> m_buffer;
-		SpinLock m_lock;
 		Semaphore m_semaphore;
 
 		uint32_t m_writing_count { 1 };