KVM: x86/cpuid: add type suffix to decimal const 48 fix building warning

KVM: x86/cpuid: add type suffix to decimal const 48 fix building warning

The default type of a decimal constant is determined by the magnitude of
its value. If the value falls within the range of int, its type is int;
otherwise, if it falls within the range of unsigned int, its type is
unsigned int. This results in the constant 48 being of type int. In the
following min call,

g_phys_as = min(g_phys_as, 48);

This leads to a building warning/error (CONFIG_KVM_WERROR=y) caused by
the mismatch between the types of the two arguments to macro min. By
adding the suffix U to explicitly declare the type of the constant, this
issue is fixed.

Signed-off-by: Ethan Zhao <haifeng.zhao@linux.intel.com>
Link: https://lore.kernel.org/r/20250127013837.12983-1-haifeng.zhao@linux.intel.com
Signed-off-by: Sean Christopherson <seanjc@google.com>