x86/bugs: Drop unnecessary export of "x86_spec_ctrl_base"

Don't export x86_spec_ctrl_base as it's used only in bugs.c and process.c,
neither of which can be built into a module.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://patch.msgid.link/20251112173944.1380633-2-seanjc%40google.com

Author: sean-jc

arch/x86/kernel/cpu/bugs.c

@@ -102,7 +102,6 @@ static void __init vmscape_apply_mitigation(void);
 
 /* The base value of the SPEC_CTRL MSR without task-specific bits set */
 u64 x86_spec_ctrl_base;
-EXPORT_SYMBOL_GPL(x86_spec_ctrl_base);
 
 /* The current value of the SPEC_CTRL MSR with task-specific bits set */
 DEFINE_PER_CPU(u64, x86_spec_ctrl_current);