erts: Do not use named no_cpuid label in asm

Ask compiler to generate unique label name. Using named label has implications
on optimizer, that may lead to the compilation errors as the following:

    pthread/ethread.c: Assembler messages:
    pthread/ethread.c:213: Error: symbol `no_cpuid' is already defined
    pthread/ethread.c:213: Error: symbol `no_cpuid' is already defined
    pthread/ethread.c:213: Error: symbol `no_cpuid' is already defined

erts/lib_src/pthread/ethread.c

@@ -208,9 +208,9 @@ ethr_x86_cpuid__(int *eax, int *ebx, int *ecx, int *edx)
              "popl %%eax\n\t"
              "movl $0x0, %0\n\t"
              "xorl %%ecx, %%eax\n\t"
-             "jz no_cpuid\n\t"
+             "jz %=f\n\t"
 	     "movl $0x1, %0\n\t"
-             "no_cpuid:\n\t"
+             "%=:\n\t"
              : "=r"(have_cpuid)
              :
              : "%eax", "%ecx", "cc");