Kernel: Remove obsole CPUID::IsAvailable

This is now a harware requirement that is verified already in boot.S

kernel/arch/i386/APIC.cpp

@@ -341,12 +341,6 @@ namespace APIC
 
 	static bool InitializeAPIC()
 	{
-		if (!CPUID::IsAvailable())
-		{
-			kprintln("CPUID not available");
-			return false;
-		}
-
 		uint32_t ecx, edx;
 		CPUID::GetFeatures(ecx, edx);
 		if (!(edx & CPUID::Features::EDX_APIC))

kernel/arch/i386/CPUID.cpp

@@ -12,24 +12,6 @@ namespace CPUID
 		asm volatile ("cpuid": "=a"(out[0]), "=b"(out[0]), "=d"(out[1]), "=c"(out[2]) : "a"(code));
 	}
 
-	bool IsAvailable()
-	{
-		uint32_t res;
-		asm volatile(
-			"pushfl;"
-			"pushfl;"
-			"popl %0;"
-			"xorl %1, %0;"
-			"pushl %0;"
-			"popfl;"
-			"pushfl;"
-			"popl %0;"
-			"popfl;"
-			: "=r"(res)
-			: "i" (0x00200000));
-		return res != 0;
-	}
-
 	const char* GetVendor()
 	{
 		static char vendor[13] {};
@@ -48,9 +30,6 @@ namespace CPUID
 
 	bool Is64Bit()
 	{
-		if (!IsAvailable())
-			return false;
-		
 		uint32_t buffer[4] {};
 		get_cpuid(0x80000000, buffer);
 		if (buffer[0] < 0x80000001)

kernel/include/kernel/CPUID.h

@@ -148,7 +148,6 @@ namespace CPUID
 		}
 	}
 
-	bool IsAvailable();
 	const char* GetVendor();
 	void GetFeatures(uint32_t& ecx, uint32_t& edx);
 	bool Is64Bit();

kernel/kernel/Shell.cpp

@@ -125,11 +125,6 @@ namespace Kernel
 				TTY_PRINTLN("'cpuinfo' does not support command line arguments");
 				return;	
 			}
-			if (!CPUID::IsAvailable())
-			{
-				TTY_PRINTLN("'cpuid' instruction not available");
-				return;
-			}
 
 			uint32_t ecx, edx;
 			auto vendor = CPUID::GetVendor();
@@ -154,11 +149,6 @@ namespace Kernel
 				TTY_PRINTLN("'random' does not support command line arguments");
 				return;	
 			}
-			if (!CPUID::IsAvailable())
-			{
-				TTY_PRINTLN("'cpuid' instruction not available");
-				return;
-			}
 			uint32_t ecx, edx;
 			CPUID::GetFeatures(ecx, edx);
 			if (!(ecx & CPUID::Features::ECX_RDRND))

kernel/kernel/kernel.cpp

@@ -1,3 +1,4 @@
+#include <BAN/Memory.h>
 #include <kernel/APIC.h>
 #include <kernel/GDT.h>
 #include <kernel/IDT.h>