The modifier exists to omit the '$' when printing constants (generally
needed for insn immediates in AT&T syntax, but unwanted on e.g. data
emission directives). It's pretty odd to use it just to then stick a '$'
onto the result.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
Strictly speaking at least the [stack_mask] constraint also should be "e",
not "i".

--- a/xen/arch/x86/include/asm/current.h
+++ b/xen/arch/x86/include/asm/current.h
@@ -157,10 +157,10 @@ unsigned long get_stack_dump_bottom (uns
     "rdsspd %[ssp];"                                            \
     "cmp $1, %[ssp];"                                           \
     "je .L_shstk_done.%=;" /* CET not active?  Skip. */         \
-    ALTERNATIVE("mov $%c[shstk_base], %[val];",                 \
-                "mov $%c[shstk_base] + 8, %[val];",             \
+    ALTERNATIVE("mov %[shstk_base], %[val];",                   \
+                "mov %[shstk_base] + 8, %[val];",               \
                 X86_FEATURE_XEN_FRED)                           \
-    "and $%c[stack_mask], %[ssp];"                              \
+    "and %[stack_mask], %[ssp];"                                \
     "sub %[ssp], %[val];"                                       \
     "shr $3, %[val];"                                           \
     "cmp $255, %[val];" /* More than 255 entries?  Crash. */    \