Disable neon dot on unknown chipsets on aarch32 (#300)

src/arm/linux/aarch32-isa.c

diff --git a/src/arm/linux/aarch32-isa.c b/src/arm/linux/aarch32-isa.c
index 29663a7..d87a964 100644
--- a/src/arm/linux/aarch32-isa.c
+++ b/src/arm/linux/aarch32-isa.c
@@ -149,6 +149,8 @@
 			cpuinfo_log_warning("VDOT instructions disabled: cause occasional SIGILL on Unisoc T310");
 		} else if (chipset->series == cpuinfo_arm_chipset_series_unisoc_ums && chipset->model == 312) {
 			cpuinfo_log_warning("VDOT instructions disabled: cause occasional SIGILL on Unisoc UMS312");
+		} else if (chipset->vendor == cpuinfo_arm_chipset_vendor_unknown) {
+			cpuinfo_log_warning("VDOT instructions disabled: unknown chipset");
 		} else {
 			switch (midr & (CPUINFO_ARM_MIDR_IMPLEMENTER_MASK | CPUINFO_ARM_MIDR_PART_MASK)) {
 				case UINT32_C(0x4100D0B0): /* Cortex-A76 */