arm64: cpufeature: Remove redundant "feature" in reports

The word "feature" is repeated in the CPU features reporting. This drops it
for improved readability.

Before (redundant "feature" word):

 SMP: Total of 4 processors activated.
 CPU features: detected feature: 32-bit EL0 Support
 CPU features: detected feature: Kernel page table isolation (KPTI)
 CPU features: emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching
 CPU: All CPU(s) started at EL2

After:

 SMP: Total of 4 processors activated.
 CPU features: detected: 32-bit EL0 Support
 CPU features: detected: Kernel page table isolation (KPTI)
 CPU features: emulated: Privileged Access Never (PAN) using TTBR0_EL1 switching
 CPU: All CPU(s) started at EL2

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>