wlan_platform: Bring initial files for ICNSS family drivers

Bring ICNSS family drivers from msm-5.10 kernel as of commit
'cb298739ee51 ("icnss2: Download bdf file for helium targets")'
to WLAN platform project.

Updated wlan_firmware_service files and makefiles to support
ICNSS2 compilation.

Change-Id: I02cf792b61772f07ac0607be7bb6b3bfda7815e4

icnss2/power.h

@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2017-2021, The Linux Foundation. All rights reserved.
+ */
+
+#ifndef __ICNSS_POWER_H__
+#define __ICNSS_POWER_H__
+
+int icnss_hw_power_on(struct icnss_priv *priv);
+int icnss_hw_power_off(struct icnss_priv *priv);
+int icnss_get_clk(struct icnss_priv *priv);
+int icnss_get_vreg(struct icnss_priv *priv);
+int icnss_init_vph_monitor(struct icnss_priv *priv);
+void icnss_put_resources(struct icnss_priv *priv);
+void icnss_put_vreg(struct icnss_priv *priv);
+void icnss_put_clk(struct icnss_priv *priv);
+int icnss_vreg_unvote(struct icnss_priv *priv);
+
+#endif