Revert "hw/i386: pass RNG seed via setup_data entry"

This reverts commit 67f7e426e5.

Additionally to the automatic revert, I went over the code
and dropped all mentions of legacy_no_rng_seed manually,
effectively reverting a combination of 2 additional commits:

    commit ffe2d2382e
    Author: Jason A. Donenfeld <Jason@zx2c4.com>
    Date:   Wed Sep 21 11:31:34 2022 +0200

        x86: re-enable rng seeding via SetupData

    commit 3824e25db1
    Author: Gerd Hoffmann <kraxel@redhat.com>
    Date:   Wed Aug 17 10:39:40 2022 +0200

        x86: disable rng seeding via setup_data

Fixes: 67f7e426e5 ("hw/i386: pass RNG seed via setup_data entry")
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Dov Murik <dovmurik@linux.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
(cherry picked from commit 167f487358)
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Mjt: this required manual edit for stable-7.2

include/hw/i386/pc.h

@@ -128,9 +128,6 @@ struct PCMachineClass {
 
     /* create kvmclock device even when KVM PV features are not exposed */
     bool kvmclock_create_always;
-
-    /* skip passing an rng seed for legacy machines */
-    bool legacy_no_rng_seed;
 };
 
 #define TYPE_PC_MACHINE "generic-pc-machine"

include/hw/i386/x86.h

@@ -126,8 +126,7 @@ void x86_bios_rom_init(MachineState *ms, const char *default_firmware,
 void x86_load_linux(X86MachineState *x86ms,
                     FWCfgState *fw_cfg,
                     int acpi_data_size,
-                    bool pvh_enabled,
-                    bool legacy_no_rng_seed);
+                    bool pvh_enabled);
 
 bool x86_machine_is_smm_enabled(const X86MachineState *x86ms);
 bool x86_machine_is_acpi_enabled(const X86MachineState *x86ms);